Answer:
x = 6
Step-by-step explanation:
You want the value of x in the geometry where an angle bisector has divided a triangle into sides 42 and (6x-1), and corresponding sides 78 and (10x+5).
ProportionThe angle bisector divides the sides of the triangle proportionally:
(6x -1)/42 = (10x +5)/78
13(6x -1) = 7(10x +5) . . . . . . . . multiply by 546
78x -13 = 70x +35 . . . . . . . simplify
8x = 48 . . . . . . . . . . . . . . add 13-70x
x = 6 . . . . . . . . . . . . . . divide by 8
What is the rage of g(x)?
The graph of f(x) = 1/2(2.5)x and it’s reflection across the x-axis, g(x), are shown.
The range of g(x) is all real numbers less than 0.
An easy definition of a function?
As a set of inputs with one output for each, a function is defined as a relationship between them.
A function, expressed simply, is an association between inputs where each input is connected to one and only one output.
The given function is
f(x) = 1/2(2.5)ˣ
If a graph reflected across x axis, then
(x,y) ⇒ (x, -y )
The function f(x) reflected across x-axis, so
g(X) = -f(x)
g(X) = -1/2(2.5)ˣ
It is an exponential function.
g(x) ⇒ -∞ as x⇒ ∞
g(X) ⇒ 0 as x ⇒ - ∞
Since the value of g(x) lies between ∞ and 0, therefore the range of g(x) is all real numbers less than 0.
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1/4y= 5x
Tell whether the equation represents a direct proportion. If so, identify the constant of proportionality.
Yes, the equation 1/4y = 5x represents a direct proportion, and has a constant of proportionality of
How to Identify a Direct Proportion Equation?A direct proportion is defined by the equation, y = kx, where k is the constant of proportionality.
To check if see the equation is a direct proportion, multiply both sides of the equation by 4:
1/4y * 4 = 4 * 5x
y = 20x
This shows that the ratio of y to x is equal to a constant value of 20, so y and x are directly proportional. The constant of proportionality is 20.
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A company dyes two sizes of rugs. A small rug requires 8 hours for dyeing, and a medium-size rug requires 12 hours for dyeing. The dyers have to make at least 22 rugs, and they must do it in less than 240 hours. Let x equal small rugs and y equal medium rugs. Which of the following inequalities can be paired with x + y ≥ 22 to create a system that represents this situation?
8x + 12y > 240
12x + 8y > 240
8x + 12y < 240
12x + 8y < 240
The suitable inequality is 8x + 12y < 240
What is an inequality?Inequalities are the relationship two expressions which states that the two expressions are not equal. It is denoted by the symbols like < , >, ≤, ≥.
Given that x equal small rugs and y equals medium rugs.
A company needs 8 hours for dyeing small rugs then, 8x.
And it needs 12 hours for dyeing medium rugs then, 12y.
The company must do 22 rugs less than 240 hours.
So the inequality is 8x + 12y < 240, it is paired with x + y ≥ 22.
Hence the suitable inequality is 8x + 12y < 240.
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If f(x)=2(x)+3=5 what is f(-2)
As a result, f(-2) has a value of -1 by simply substituting the value of x in the function. as Each function is given a domain and a codomain, often known as a scope.
what is function ?Math deals with numbers with their variants, formulae and adjacent tissues, structures and associated locations, and areas where they might be found. The term "function" refers to the connection between a series of inputs, of which each has a corresponding output. A function is a connection between the inputs and outputs where each input result in a single, unique output. A domain as well as a codomain, or scope, are allocated to each function. Functions are generally symbolized by the letter f. (x). The input is an x. On functions, another functions, many-to-one functions, within operations, and on functions are the four main types of functions that are available.
given
f(x)=2(x)+3=5
= f(-2) = 2(-2) + 3 = 5
= -4 + 3
= -1
As a result, f(-2) has a value of -1 by simply substituting the value of x in the function. as Each function is given a domain and a codomain, often known as a scope.
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45 medals were given out at a band competition. There were 22 bronze medals and 14 silver medals. The rest were gold medals. What percentage of medals were gold medals?
Answer:
20%
Step-by-step explanation:
45
22 bronze
14 silver
so 45- 22 -14 =9 gold
9/45 = 1/5 =20%
The scatter plot shows the number of years of experience, x , and the amount charged per hour, y , for each of 24 dog sitters in Texas. (a) Write an approximate equation of the line of best fit for the data. It doesn't have to be the exact line of best fit. (b) Using your equation from part (a), predict the amount charged per hour by a dog sitter with 10 years of experience.
a) An approximate equation of the line of best fit for the data is,
⇒ y = 18/13 (x - 7)
b) The amount charged per hour by a dog sitter with 10 years of experience is, $54/13
What is Equation of line?The equation of line in point-slope form passing through the points
(x₁ , y₁) and (x₂, y₂) with slope m is defined as;
⇒ y - y₁ = m (x - x₁)
Where, m = (y₂ - y₁) / (x₂ - x₁)
Given that;
The scatter plot shows the number of years of experience, x , and the amount charged per hour, y , for each of 24 dog sitters in Texas.
Now, Add a line of best fit (see attached).
Here, The two points on the line are,
⇒ (7, 0) and (20, 18)
Thus, Use these points to find the slope of the line is,
⇒ m = (18 - 0) / (20 - 7)
⇒ m = 18 / 13
Use the found slope and one of the points in the point-slope form of the linear equation to find an equation for the line of best fit:
⇒ y - y₁ = m (x - x₁)
⇒ y - 0 = 18/13 (x - 7)
⇒ y = 18/13 (x - 7)
Substitute x = 10 we get;
⇒ y = 18/13 (x - 7)
⇒ y = 18/13 (10 - 7)
⇒ y = 18/13 × 3
⇒ y = $54/13
Thus, An approximate equation of the line of best fit for the data is,
⇒ y = 18/13 (x - 7)
b) The amount charged per hour by a dog sitter with 10 years of experience is, $54/13
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PLEASEEE ANSWER FAST THIS IS TIMED Bernadette throws the javelin for her school’s track and field team. The graph below shows the height and horizontal distance traveled by the javelin for three of Bernadette’s practice throws.
Use the graph to determine the average rate of change over the interval (0,20) for Throw #3. To earn full credit, show your work using a method explained in the Orientation.
Answer:
Step-by-step explanation:
Average ROC is [tex]Change=\frac{f(b)-f(a)}{b-a} \\[/tex] so we need to look at the points (0,20) at 0 our y is 6 and at 20 its 12 so we have (0,6) and (20,12) we now use our formula so we have Change=[tex]\frac{12-6}{20-0} =\frac{6}{20} =\frac{3}{10}[/tex] so our answer is 3/10
true or false? the following is a valid proof of the theorem that for every integer n, there is an integer k such that n < k < n 2. assume n is an integer. let k be an integer such that n < k < n 2. this shows that for every n, an integer k such that n < k < n 2 exists.
False. The given statement is not a valid proof of the theorem because it is circular.
The proof starts with the assumption that there exists an integer k such that n < k < n^2 and then uses this assumption to conclude that the theorem is true. However, this does not actually prove the existence of k, it simply restates the theorem. A valid proof would need to start with some other set of premises and use logical deduction to arrive at the conclusion that such a k exists. The given statement is not sufficient to establish the truth of the theorem.
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If a 1/4 of Rihanna's savings is $200 what is her entire savings?
Answer:
800
Step-by-step explanation:
1/4 =200
200+200 =2/4
200+200+200+200 =4/4 = all = 800
Answer:
Step-by-step explanation:
$800
Which pair shows 2 equivalent expressions?
A, 3d, d+d+d+3
B. 2g+g-2g,2g
C. 4y, y+y+2y
D. h+h+1, 3h
Answer:
C
Step-by-step explanation:
add each of them all up and you'll see only C 4y = the sum
Zoe plans to do the scarf. She wants the scarf to be more than one but less than 1.5 feet wide, and more than six but less than 8 feet long. Graph all possible dimensions of Zoe scarf. There’s two possible combinations.
On solving the provided question, we can say that the inequality that will be formed is [tex]1\leq x\leq 1.5 and 6\leq y\leq 8[/tex] and Two possible combinations are (1.25.7). (1.35.7.5)
What is inequality?An inequality in mathematics is a relationship between two expressions or values that is not equal. Thus, imbalance leads to inequality. An inequality creates the link between two values that are not equal in mathematics. Egality is distinct from inequality. When two values are not equal, most commonly use the not equal sign (). Different inequalities are used to contrast values, no matter how little or large. Many simple inequalities may be resolved by modifying the two sides until the variables are all that remain. But a number of things contribute to inequality: Negative values on both sides are divided or added. Trade off the left and right.
the inequality that will be formed is
[tex]1\leq x\leq 1.5\\6\leq y\leq 8[/tex]
Two possible combinations are (1.25.7). (1.35.7.5)
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The mathematical constant pi is needed when calculating the area of a
When computing the area of a circle, the mathematical constant pi () is required. Pi is the circumference-to-diameter ratio of a circle and is approximately equal to 3.14159.
The area of a circle is calculated by multiplying pi by the radius squared (r2). To estimate the area of a circle, utilize pi in the calculation since it is a vital aspect of the relationship between the circumference and diameter of a circle.
Pi is not required when determining the area of a square, rectangle, or cube since the formulas for these shapes are different.
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The question is -
The mathematical constant pi is needed when calculating the area of a _.
a. circle
b. square
c. rectangle
d. cube
Please help me! thank you
Suppose an object is thrown upward with initial velocity of 48 feet per second from a high of 120 feet. The height of the object t seconds after it is thrown is given by h(t)=-16t^2+48t+120. Find the average velocity from t=2 to t=4.
Type your answer as a number with no units.
The average velocity from t = 2s to t = 4s would be - 48 ft/s.
What are algebraic expressions?In mathematics, an expression or mathematical expression is a finite combination of symbols that is well-formed according to rules that depend on the context.
Mathematical symbols can designate numbers (constants), variables, operations, functions, brackets, punctuation, and grouping to help determine order of operations and other aspects of logical syntax.
Given is that an object is thrown upward with initial velocity of 48 feet per second from a high of 120 feet. The height of the object t seconds after it is thrown is given by h(t) = - 16t² + 48t + 120.
Average velocity
Average rate of change of velocity with time is called average velocity. Mathematically -
v{avg.} = Δx/Δt .... Eq { 1 }
Δx = x(4) - x(2)
Δx = - 16(4)² + 48(4) + 120 - {- 16(2)² + 48(2) + 120}
Δx = - 96
Δt = 4 - 2 = 2
So -
v{avg.} = Δx/Δt = -96/2 = - 48 ft/s
Therefore, the average velocity from t = 2s to t = 4s would be - 48 ft/s.
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What is 35% of ? Is 220
The value of the unknown is 628.57
What is percentage?Percent simply means "per hundred" and the symbol used to express percentage is %. One percent (or 1%) is one hundredth of the total or whole and is therefore calculated by dividing the total or whole number by 100. Example: 1% of 250 = (1 ÷ 100) x 250 = 2.5.
Represent the unknown by x
therefore;
35/100 × x = 220
multiply both sides by 100
35x = 22000
x = 22000/35
x = 628.57
therefore 35% of 628.57 is 220
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Evaluate the expression for v = 2 and w = 16.
w − 7|v| =
Answer:
2
Step-by-step explanation:
Substituting v = 2 and w = 16 in the expression w - 7|v|, we get:
w - 7|v| = 16 - 7|2|
We need to evaluate the absolute value of 2, which is simply 2. Therefore, we can simplify the expression as:
16 - 7|2| = 16 - 7(2) = 16 - 14 = 2
So, w - 7|v| = 2 when v = 2 and w = 16.
Angelique builds a fence. After working for 2 5/6 hours, she has 5/8 of the fence. Can Angelique build the entire fence in 5 hours if she continues to build at the same rate?
PLEASE HELP, FAST!
Answer:
yes
Step-by-step explanation:
working for 2 5/6 hours, she has 5/8 of the fence.
so per hour = 5/8 ÷ 2 5/6 =15/68 per hour
5 hours she'll do: 15/68*5 = 75/68
75 >68
so yes she will finish it
if the probability that a portfolio outperforms its benchmark in any quarter is 0.75, the probability that the portfolio outperforms its benchmark in three or fewer quarters over the course of a year is closest to: 0.26 0.42 0.68
The closest solution to this total among the available possibilities is 0.68, indicating that the portfolio is likely to surpass its benchmark in three or fewer quarters over the course of a year.
What is probability?The field of mathematics concerned with probability is known as probability theory. Although there are various distinct interpretations of probability, probability theory approaches the idea rigorously mathematically by articulating it through a set of axioms.
Here,
The probability that the portfolio outperforms its benchmark in three or fewer quarters over the course of a year is the sum of the probabilities of outperforming the benchmark in exactly 0 quarters, 1 quarter, 2 quarters, and 3 quarters.
Since the probability of outperforming the benchmark in any quarter is 0.75, the probability of not outperforming the benchmark in a quarter is 1 - 0.75 = 0.25.
The probability of not outperforming the benchmark in exactly 0 quarters is 0.25⁰ = 1
The probability of not outperforming the benchmark in exactly 1 quarter is 0.25¹= 0.25
The probability of not outperforming the benchmark in exactly 2 quarters is 0.25² = 0.0625
The probability of not outperforming the benchmark in exactly 3 quarters is 0.25³ = 0.015625
So, the probability of outperforming the benchmark in exactly 0 quarters, 1 quarter, 2 quarters, and 3 quarters is 1 - 0.25⁰, 1 - 0.25¹, 1 - 0.25², and 1 - 0.25³, respectively.
The sum of these probabilities is the probability of outperforming the benchmark in three or fewer quarters over the course of a year:
P(outperform in three or fewer quarters) = 1 - 0.25⁰ + 1 - 0.25¹ + 1 - 0.25² + 1 - 0.25³
This expression can be calculated to get an exact answer, but to get the closest answer to the options given, we can round off the intermediate results to 2 decimal places:
P(outperform in three or fewer quarters) = 1 + 0.75 + 0.94 + 0.98
The closest answer to this sum among the options given is 0.68, so the probability that the portfolio outperforms its benchmark in three or fewer quarters over the course of a year is closest to 0.68.
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A child must weigh no more than 34.5 pounds to ride in a particular car seat. A child weighs 36.269 pounds. By how many pounds does the child exceed the weigh limit?
Answer:
1.769 pounds
Step-by-step explanation:
36.269 - 34.5 = 1.769
How many different possible outcomes are there if you spim
a spinner labeled Red, Blue, Yellow four times?
The number of different possible outcomes when we spin the spinner is; 81
How to find the number of possible outcomes?The given parameters are:
Spinner section, n = 3 i.e. Red, Blue, Yellow
Number of spins, r = 4
The number of possible outcomes is calculated using the formula for these type of outcomes is:
Number of outcomes = n^r
So we have:
Outcomes = 3⁴
Outcomes = 81
Hence, the number of outcomes is 81
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if you graphed the data points in a particular time series and a relatively flat, horizontal pattern was observed, the method that should be used to forecast the next point in the series would be
The correct answer is e, none of the above, as a relatively flat, horizontal pattern indicates the absence of a trend or seasonality making it difficult to use any of the mentioned methods for forecasting.
This type of pattern is commonly referred to as a "stationary time series" and may require different forecasting techniques such as moving averages or ARIMA models.
A stationary time series means that the statistical properties of the series, such as the mean and variance remain constant over time. This type of series may still exhibit random fluctuations and noise that need to be accounted for in the forecasting process. Moving averages are commonly used to smooth out the noise and highlight any underlying patterns in the data.
This question should be provided with answer choices, which are;
a. A horizontal method.b. An alpha method.c. A beta method.d. C trend analysis method.e. None of the above.Learn more about time series brainly.com/question/30698222
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What would the polynomial be?
The options are:
monomial
binomial
trinomial
none of the above
Answer:
Trinomial
Step-by-step explanation:
A trinomial is an algebraic expression with three, unlike terms.
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let f(x) = e^x and g(x) = x + 6. what are the domain and range of (gof)(x)?
Domain and range of the composite function (gof)(x) formed by given f(x) and g(x) is equal to all positive real numbers and y > 6 , y ∈R respectively.
Function f(x ) is :
f(x) = e^x
Function g(x) is :
g(x) = x + 6
To find the range of composite function (gof)(x) simplify the function .
(gof)(x)
= g ( f(x))
Substitute f(x) = e^x we get
= g ( e^x )
Replace x by e^x in g(x) we get,
= e^x + 6
Domain of the composite function is given by all the value based on e^x that is all positive real numbers.
Range is translated by 6.
y > 6 , y∈ R ( positive real numbers)
Therefore, the domain and range of composite function (gof)(x) is all positive real numbers and y > 6 , y∈ R ( positive real numbers) respectively.
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Stanley invests £7500 for 4 years in a savings account.
The savings account pays compound interest at a rate of x% per year.
At the end of 4 years the investment is worth £7866.53
Work out the value of x.
Give your answer correct to 1 decimal place.
Answer:
91.63%
Step-by-step explanation:
The annual interest rate is 1.2% if Stanley invests £7500 for 4 years in a savings account.
What is Percentage?percentage, a relative value indicating hundredth parts of any quantity.
We can use the formula for compound interest:
[tex]A = P (1 + r/n)^(^n^t^)[/tex]
where A = the final amount, P = the principal (initial investment), r = the annual interest rate (as a decimal), n = the number of times the interest is compounded per year and t = the time in years
We know that P = £7500, t = 4 years, and A = £7866.53.
Let n is 1
Plugging in the values we know, we get:
£7866.53 = £7500 (1 + r/1)⁴
Simplifying the equation:
(1 + r)⁴ = 1.04887
Taking the fourth root of both sides:
1 + r = 1.012
Subtracting 1 from both sides:
r = 0.012 or 1.2%
Therefore, the annual interest rate is 1.2%.
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The question is attached below!
-Ty! :)
$612.50.
Step-by-step explanation:
First you find 3.5% of $3500.Which is $122.50.Then multiply $122.50 by 5 years.So then your answer will be $612.50.which box plot a, b, or c is a reasonable summary of the data used to create the histogram? there are 16 data points.
The boxplot which is reasonable to the summary of the data used to create the histogram is equals to boxplot A. So, correct answer is option (c).
Histogram is a graph which discribes the distribution of data by using of bars of different heights and same width. In this problem, we'll have a histogram and 3 box plots as box plot A, box plot B and box plot C, and we have to choose here which of these 3 box spots is a reasonable summary of the data. We can see that the histogram in above figure is skewed to left because it's maximum data present on the right end. The box plot C, is representing a normally distributed data, but are data is right side distributed so, it is wrong. Similarly, as we see box plot B shows distribution of data in left end, which is also not right choice. So, boxplot A is correct because it's showing the maximum data and the median where we have. We can see the median line over her median on the right hand. Thus, data is very highly negatively skewed hence boxplot A is appropriate.
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Complete question:
See the above figure, which box plot a, b, or c is a reasonable summary of the data used to create the histogram? there are 16 data points.
a) boxplot C
b) boxplot B
c) boxplot A
A recipe for chocolate chips uses 3 tablespoons of cookie batter for every 2 tablespoons of chocolate chips. Use b for the number of tablespoons of cookie batter and use c for the number of tablespoons of chocolate chips .
I’m so confused
is the line through points p(-8,-10) and q(-5,-12) perpendicular to the line through points r(9,-6) and s(17,-5)
we dunno, hmmm let's check for the slope for PQ
[tex]P(\stackrel{x_1}{-8}~,~\stackrel{y_1}{-10})\qquad Q(\stackrel{x_2}{-5}~,~\stackrel{y_2}{-12}) \\\\\\ \stackrel{slope}{m}\implies \cfrac{\stackrel{\textit{\large rise}} {\stackrel{y_2}{-12}-\stackrel{y1}{(-10)}}}{\underset{\textit{\large run}} {\underset{x_2}{-5}-\underset{x_1}{(-8)}}} \implies \cfrac{-12 +10}{-5 +8} \implies \cfrac{ -2 }{ 3 } \implies - \cfrac{2 }{ 3 }[/tex]
keeping in mind that perpendicular lines have negative reciprocal slopes, then if both are truly perpendicular, then line RS will have a slope of
[tex]\stackrel{~\hspace{5em}\textit{perpendicular lines have \underline{negative reciprocal} slopes}~\hspace{5em}} {\stackrel{slope}{ \cfrac{-2}{3}} ~\hfill \stackrel{reciprocal}{\cfrac{3}{-2}} ~\hfill \stackrel{negative~reciprocal}{-\cfrac{3}{-2} \implies \cfrac{3}{ 2 }}}[/tex]
let's see if that's true
[tex]R(\stackrel{x_1}{9}~,~\stackrel{y_1}{-6})\qquad S(\stackrel{x_2}{17}~,~\stackrel{y_2}{-5}) \\\\\\ \stackrel{slope}{m}\implies \cfrac{\stackrel{\textit{\large rise}} {\stackrel{y_2}{-5}-\stackrel{y1}{(-6)}}}{\underset{\textit{\large run}} {\underset{x_2}{17}-\underset{x_1}{9}}} \implies \cfrac{-5 +6}{8} \implies \cfrac{ 1 }{ 8 } ~~ \bigotimes ~~ \textit{not perpendicular}[/tex]
Answer:
Step-by-step explanation:
No they are not perpendicular.
Perpendicular lines have slopes that are negative reciprocals of each other.
PQ slope = -12 - -10/-5 --8 = -2/3
RS slope = -5 - -6/17 -9 = 1/8
Slope are not negative reciprocals - the lines are not perpendicular.
Slope formula is m = y2 - y1/x2 - x1
Use this to determine slope.
For example if the the slope of RS was 3/2 - the lines would be perpendicular.
Given the proportional equation y = -5x, what is the value of y when x = 6
When x = 6, the value of y is:
y = -5x
y = -5(6)
y = -30
Therefore, when x = 6, y is equal to -30.
Answer:
-30
Step-by-step explanation:
given,
y = -5x
x = 6
Now,
y = -5x
or, y = -5(6)
therefore, y = -30
Which of the following points lie on a line that passes through the origin with a slope of −2/5? Select all that apply.
(−5, 2) is point lie on a line that passes through the origin with a slope of −2/5
What is Slope of Line?The slope of the line is the ratio of the rise to the run, or rise divided by the run. It describes the steepness of line in the coordinate plane.
The slope intercept form of a line is y=mx+b, where m is slope and b is the y intercept.
The slope of line passing through two points (x₁, y₁) and (x₂, y₂) is
m=y₂-y₁/x₂-x₁
We need to find the points lie on a line that passes through the origin with a slope of −2/5
The line passes through (0, 0) and (x, y) form a slope of -2/5
-2/5=y/x
So y is 2 and x is 5.
Hence, (−5, 2) is points lie on a line that passes through the origin with a slope of −2/5
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equation in point slope from of slope of 0.25 and point of (5,-2)
The equation is correct and the point (5,-2) is on the line.
The point slope equation of a line with slope 0.25 and a point (5,-2) would be y-(-2) = 0.25(x-5). This equation can be rearranged to y = 0.25x - 1.5.
Calculation:
y = 0.25x - 1.5
Plugging in x = 5
y = 0.25(5) - 1.5
y = -2
The point (5,-2) is on the line.
The point slope equation of a line with slope 0.25 and a point (5,-2) can be written as y-(-2) = 0.25(x-5) which can further be rearranged to y = 0.25x - 1.5. This equation can be further tested by plugging in the x value of the point (5) into the equation and the y value of the point (-2) should be obtained. This proves that the equation is correct and the point (5,-2) is on the line.
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