The vertice of triangle ABC are A(8,4), B(6,3) and C(5-5). Find the angle between the side AB and BC.
Answer:
Step-by-step explanation:
Use law of cosines
c² = a² + b² - 2abcosθ
cosθ = (c² - a² - b²) / -2ab
c = length of AC = √(8 - 5)² + (4 - (-5))² = √90
b = length of AB = √(8 - 6)² + (4 - 3)² = √5
a = length of BC = √(6 - 5)² + (3 - (-5))² = √65
cosθ = (√90² - √65² - √5²) / -2√65√5
cosθ = 20 / -36.05551...
cosθ = - 0.5547001
θ = 123.69°
x squared+ y squared = 2 y = 2x squared – 3 Which of the following describes the system?
Answer:
[tex]x=-1,1,-\sqrt{\frac{7}{4} },\sqrt{\frac{7}{4}}[/tex] and [tex]y=-1,\frac{1}{2}[/tex]
The ordered pair solutions are [tex](-\sqrt{\frac{7}{4}},0.5)[/tex], [tex](\sqrt{\frac{7}{4}},0.5)[/tex], [tex](-1,-1)[/tex], and [tex](1,-1)[/tex].
Step-by-step explanation:
I'm assuming the system is [tex]\left \{ {x^2+y^2=2} \atop {y=2x^2-3}} \right.[/tex]:
[tex]x^2+y^2=2[/tex]
[tex]x^2+(2x^2-3)^2=2[/tex]
[tex]x^2+(4x^4-12x^2+9)=2[/tex]
[tex]x^2+4x^4-12x^2+9=2[/tex]
[tex]4x^4-11x^2+9=2[/tex]
[tex]4x^4-11x^2+7=0[/tex]
[tex]x^4-11x^2+28=0[/tex]
[tex](x^2-7)(x^2-4)=0[/tex]
[tex](4x^2-7)(x^2-1)=0[/tex]
[tex]4x^2-7=0[/tex]
[tex]4x^2=7[/tex]
[tex]x^2=\frac{7}{4}[/tex]
[tex]x=\pm\sqrt{\frac{7}{4}}[/tex]
[tex]x^2-1=0[/tex]
[tex]x^2=1[/tex]
[tex]x=\pm1[/tex]
[tex]y=2x^2-3[/tex]
[tex]y=2(\pm\sqrt{\frac{7}{4}})^2-3[/tex]
[tex]y=2({\frac{7}{4}})-3[/tex]
[tex]y=\frac{7}{2}-3[/tex]
[tex]y=\frac{1}{2}[/tex]
[tex]y=2x^2-3[/tex]
[tex]y=2(\pm1)^2-3[/tex]
[tex]y=2(1)-3[/tex]
[tex]y=2-3[/tex]
[tex]y=-1[/tex]
Therefore, [tex]x=-1,1,-\sqrt{\frac{7}{4} },\sqrt{\frac{7}{4}}[/tex] and [tex]y=-1,\frac{1}{2}[/tex]
The ordered pair solutions are [tex](-\sqrt{\frac{7}{4}},0.5)[/tex], [tex](\sqrt{\frac{7}{4}},0.5)[/tex], [tex](-1,-1)[/tex], and [tex](1,-1)[/tex].
PLEASE HELP WILL MARK BRAINIEST!!!!!
Answer:
a perpendicular line from a point on ab
A train leaves a point A at 5 pm and reach another point B at 11 pm. Another train leaves point B at 7 pm and reach point A at 10 pm. At what point will the two trains meet?
Step-by-step explanation:
let's think this through.
train a goes from A to B in 6 hours. that means with a speed of 1/6 / hour.
train b goes from B to A in 3 hours, so it is twice as fast as train a = 2/6 / hour.
when train b leaves B (at 7pm), train a was already traveling for 2 hours (1/3 of the whole trip) leaving it with 4 hours to go (2/3 if the distance).
that means that at that point now both trains are moving against each other with a relative speed of 3 times the
speed of a (the original speed of a plus the double speed of b).
this is the same as one train standing, and the other going the whole distance with 3 times the speed of a.
the whole distance is 2/3 of AB.
the speed is 3/6 / hour = 1/2 / hour.
so, a single train with that speed would cover the total distance AB in 2 hours. or half of the distance in 1 hour.
the question now, how long for 2/3 of AB.
the distances relate by a factor :
1/2 × f = 2/3
f = 2/3 / 1/2 = 2/3 × 2/1 = 4/3
now we need to multiply also the time in the distance/time speed ratio by this factor.
therefore, 2/3 of the total distance is done in 1×4/3 = 4/3 of an hour.
that means both trains meet after 4/3 of an hour after 7pm.
that is 7pm plus 1 hour and 20 minutes giving us 8:20pm.
As a hurricane approaches, the air temperature changes −7.8°F every hour.
Which value represents the change in air temperature over 1.25 hours?
−9.75°F
−9.05°F
−6.55°F
−6.24°F
The change in air temperature over 1.25 hours is -9.75°F
A linear equation is in the form:
y = mx + b;
where y, x are variables, m is the rate of change and b is the initial value of y.
As a hurricane approaches, the air temperature changes −7.8°F every hour. The amount of change after 1.25 hours is:
Change = −7.8°F every hour * 1.25 hours
Change = -9.75°F
Therefore the change in air temperature over 1.25 hours is -9.75°F
Find out more on linear equation at: https://brainly.com/question/14323743
I need help asap very struggle with math
Answer:
16feet
part B is 18 feed for a good at a better than the price but the one
The pool at "Splash Around" is open for 14 weeks during the summer. You can swim for $6 a session, or you can buy membership for
$100 and pay only $4 a session. Which equation would you use to determine how many sessions you must use the pool to justify
buying the membership?
Answer:
Step-by-step explanation:
if x is the number of times you go swimming
100 + 4x < 6x
Out of an 98 day season
If you attend 50 days, the cost is $300 either with or without the membership
Less than 50 days, it's less expensive to just pay the daily rate.
More than 50 days, it's less expensive to have the membership.
Seven less than one-fourth of a number is 2. What is the number?
Based on the equation given, it can be deduced that the value of the number will be 36.
Let the number be represented by x
Therefore, seven less than one-fourth of a number will be:
=(1/4 × x) - 7
= 0.25x - 7
Now, seven less than one-fourth of a number is 2 will be written as:
0.25x - 7 = 2
0.25x = 2 + 7
0.25x = 9
x = 9/0.25
x = 36
Learn more about equation on:
https://brainly.com/question/13802812
En el siguiente trapecio calcular el valor de la base mayor x
Answer:
x = 20°
Step-by-step explanation:
OA = OB
so 140°+x°+x° = 180°
140+2x = 180
2x = 40
x = 20°
A 25-inch television has a screen that is 15 inches high. How wide is the screen?
inches
Answer:
20 inches
Step-by-step explanation:
Use the Pythagorean Theorem.
[tex]a^2 + b^2 = c^2\\15^2 + b^2 = 25^2\\225 + b^2 = 625\\b^2 = 400\\b = \sqrt{400} \\b = 20[/tex]
4.6 + 3.28 + 1.03 = ___
8.91
8.81
8.37
8.18
Answer: The answer is 8.91.
Answer : 8.91
Step - by - step explanation :
Sometimes if a question is to big for you - it's best to start off small . . .
4.60 + 3.28 = 7.88
7.88 + 1.03 = 8.91
PLEASE HELP FAILING ...A random variable x has a mean of 22 and a standard deviation of 3.1. Random samples of size 40 are drawn, and the sample mean calculated each time. What is the probability that, for a given sample, is 21?
The sample sizes are quite large, so the central limit theorem applies. (It typically does as soon as the sample size exceeds 30 or so.) This means that the sample mean will be approximately normally distributed with the same mean 22 but standard deviation 3.1/√40 ≈ 0.4902.
Now, if the question is asking about the probability of the sample mean being an exact number, that probability would be zero.
But if you meant to ask something else, like "what is the probability that the sample mean is less than 21?" then we would have a non-zero probability. In this particular case, if Y is a random variable for the sample mean, then
Pr[Y < 21] = Pr[(Y - 22)/(3.1/√40) < (21 - 22)/(3.1/√40)]
… ≈ Pr[Z < -2.0402]
… ≈ 0.0207
6 lb = how many oz .
Answer:
96 oz
Step-by-step explanation:
1 lb= 16 oz
so, 16×6=96
write an equivalent expression for 3(2z+4)
Answer:
6z+12
Step-by-step explanation:
you distribute it
Ok ok ok ok ok ok ok
Answer:
ok ok ok ok ok
Step-by-step explanation:
Answer:
ok?
Step-by-step explanation:
DUE TODAY PLZ HELP!!
Solve this system of equations using the Substitution method. Don't forget to write your final answer as a coordinate point. You must show all your work.
3x + y = -2
y = 2x + 3
The solution to the system of equations expressed as a coordinate point is [tex](x.y)=(-1,1)[/tex]
To solve the system
[tex]3x + y = -2\\y = 2x + 3[/tex]
Note that [tex]y[/tex] is already made subject of formula in [tex]y = 2x + 3[/tex]. So substitute the value for [tex]y[/tex] into [tex]3x + y = -2[/tex] to eliminate [tex]y[/tex] and leave us with an equation with [tex]x[/tex]
[tex]3x + y = -2\\3x + (2x+3) = -2\\3x+2x+3=-2\\3x+2x=-2-3\\5x=-5\\\frac{5x}{5}=\frac{-5}{5}\\x=-1[/tex]
Substitute this value of [tex]x[/tex] into [tex]y = 2x + 3[/tex] to get the value of [tex]y[/tex]
[tex]y = 2(-1) + 3\\y=-2+3\\y=1[/tex]
The solutions are [tex]x=-1,y=1[/tex], or expressed as a coordinate point
[tex](x.y)=(-1,1)[/tex]
Learn more about systems of equations here: https://brainly.com/question/16763389
solve for x. 2/x-3=x/12-4x
Answer:
x= 47 18+2 201 i ≈0.382978723+0.603295612i x= 47 −2 201 i+18 ≈0.382978723−0.603295612i Hopefully this makes just the same amount of sense as this question
If a shirt for RS 18 is marked up to RS 20 then the percentage increase is equal to
Answer:
11.1%
Step-by-step explanation:
Increase = 20 - 18
= 2
% increase= increase/initial price × 100
= 2/18 × 100
11.1%
LAST ATTEMPT IM MARKING AS BRAINLIEST!! (Pythagorean theorem )
Step-by-step explanation:
The Pythagorean theorem is:
[tex] {c}^{2} = {a}^{2} + {b}^{2} [/tex]
where c is the hypotenuse.
The two wires in the sketch are the hypotenuse so we just use the formula
let the wires=x
So:
[tex] {x}^{2} = {12}^{2} + {6}^{2} [/tex]
[tex] {x}^{2} = 144 + 36[/tex]
[tex] {x}^{2} = 180[/tex]
[tex]x = \sqrt{180} [/tex]
[tex]x = 13.42[/tex] feet
QRS is similar to XYZ.of QR=5,QS=7,and XY=30 find the value of XZ
Solve the proportion:
11/10 = 22/x
Answer:
x=20
Step-by-step explanation:
The body mass index, I, can be used to determine an individual's risk for heart disease. An index less than 25 indicates a low risk. The body mass index is given by
700W
the formula, or model, I=
where W= weight, in pounds, and H = height, in inches. Jerome is 70 inches tall. What weights will keep his body mass index
H2
between 20 and 28?
Using the BMI equation, it is found that weights between 139.4 and 195.2 pounds will keep his BMI between 20 and 28.
The BMI B, for a person of weight w(in pounds) and height h(in inches) is given by:
[tex]BMI = \frac{703w}{h^2}[/tex]
In this problem:
Height of 70 inches, hence [tex]h = 70[/tex].For a BMI of 20 inches, the weight is:
[tex]BMI = \frac{703w}{h^2}[/tex]
[tex]20 = \frac{703w}{70^2}[/tex]
[tex]w = \frac{20 \times 70^2}{703}[/tex]
[tex]w = 139.4[/tex]
For a BMI of 28 inches, the weight is:
[tex]BMI = \frac{703w}{h^2}[/tex]
[tex]28 = \frac{703w}{70^2}[/tex]
[tex]w = \frac{28 \times 70^2}{703}[/tex]
[tex]w = 195.2[/tex]
Weights between 139.4 and 195.2 pounds will keep his BMI between 20 and 28.
To learn more about the BMI, you can take a look at https://brainly.com/question/24457127
What fraction of one hour (60 minutes) is represented by the following numbers of minutes? Simplify each fraction whenever possible. A sketch of a clock might help you
15 minutes =
20 minutes =
Answer:
[tex] \frac{1}{4} [/tex]
[tex] \frac{1}{3} [/tex]
In a recent survey, it was found that 133 out of 631 randomly selected Knott's Berry Farm attendees consider Silver Bullet their favorite ride at Knott's. It was also found that 23 out of 121 randomly selected Knott's Berry Farm employees consider Silver Bullet their favorite ride. Test the hypothesis that the percentage of attendees who consider Silver Bullet their favorite ride is different than the percentage of Knott's Berry Farm employees who consider Silver Bullet their favorite ride. Use the a=.05 level of significance.
The P-value is __________, rounded to the nearest ten-thousandth (4 decimal places).
Using the z-distribution, it is found that the p-value is of 0.5975.
At the null hypothesis, it is tested if the proportions are equal, that is, their subtraction is 0, hence:
[tex]H_0: p_1 - p_2 = 0[/tex]
At the alternative hypothesis, it is tested if they are different, that is, their subtraction is not 0, hence:
[tex]H_1: p_1 - p_2 \neq 0[/tex]
The sample sizes and proportions are given by:
[tex]n_1 = 631, p_1 = \frac{133}{631} = 0.2108[/tex]
[tex]n_2 = 121, p_2 = \frac{23}{121} = 0.1901[/tex]
The standard errors are given by:
[tex]s_1 = \sqrt{\frac{0.2108(0.7892)}{631}} = 0.0162[/tex]
[tex]s_2 = \sqrt{\frac{0.1908(0.8092)}{121}} = 0.0357[/tex]
For the distribution of differences, the estimate and the standard error are:
[tex]\overline{p} = p_1 - p_2 = 0.2108 - 0.1901 = 0.0207[/tex]
[tex]s = \sqrt{s_1^2 + s_2^2} = \sqrt{0.0162^2 + 0.0357^2} = 0.0392[/tex]
The test statistic is given by:
[tex]z = \frac{\overline{p} - p}{s}[/tex]
In which [tex]p = 0[/tex] is the value tested at the null hypothesis.
Then:
[tex]z = \frac{\overline{p} - p}{s}[/tex]
[tex]z = \frac{0.0207 - 0}{0.0392}[/tex]
[tex]z = 0.528[/tex]
Using a z-distribution calculator, with a two-tailed test, as we are testing if the mean is different of a value, the p-value is of 0.5975.
A similar problem is given at https://brainly.com/question/25869410
250 + 200h = 300 + 180h
250 + 200h = 300 + 180h
− 180h − 180h
250 + 20h = 300
Answer:
h = 2.5
Step-by-step explanation:
Continue the solution by subtracting 250 from both sides.
250 -250 +20h = 300 -250
20h = 50
Divide both sides by 20
20h/20 = 50/20
h = 5/2 = 2.5
#3) They say they have 50 total coins together made up of dimes and quarters. They also say that they have $7.25 total. How many quarters do they have?
A. 10
B.15.
C.20.
D.25
Answer:
B: 15 quarters
Step-by-step explanation:
Step 1: Setup Coin Value and Coin Total Equation:
Coin Value Equation → 0.1d + 0.25q = $7.25 where d = dimes and q = quarters
Coin Total Equation → d + q = 50
Step 2: Rearrange Coin Total Equation in terms of dimes (d)
d = 50 - q ← Revised Coin Total Equation
Step 3: Plug in our Revised Coin Total Equation for d into our Coin Value Equation:
0.1(50 - q) + 0.25q = $7.25
0.1(50) - 0.1(q) + 0.25q = $7.25
5 - 0.1q + 0.25q = $7.25
5 + (0.25 - 0.1)q = $7.25
5 + 0.15q = $7.25
Step 4: Subtract 5 from each side of the equation to isolate q
5 - 5 + 0.15q = $7.25 - 5
0.15q = 2.25
Step 5: Divide each side of the equation by 0.15 to isolate q
0.15q
0.15
=
2.25
0.15
q = 15
Step 6: Using our value for q, Solve for d using our Coin Total Equation:
d + 15 = 50
Subtracting 15 from both sides, we get d + 15 - 15 = 50 - 15
d = 35
Summarizing our word problem, we see that 15 quarters and 35 dimes adds up to $7.25
A line passes through the point (-4, 7) and has a slope of -5/4
Write an equation in slope-intercept form for this line.
Answer:
[tex]y=-\frac{5}{4} x+2.[/tex]
Step-by-step explanation:
1) slope-interception form is: y=s*x+i, where 's' and 'i' are slope and interception;
2) according to the condition s= -5/4, then the required equation is: y= -5/4 *x +i, where i - interception;
3) if to substitute (-4;7) into the required equation y= -5/4 *x +i, it is possible to calculate 'i':
7= -5/4*(-4)+i; ⇒i=2, then
[tex]4) \ finally, \ y=-\frac{5}{4}x+2.[/tex]
A bookstore had 25 copies of a magazine. Yesterday the bookstore sold 3/5 of these coples. How many copies were sold yesterday?
Answer:
15
Step-by-step explanation:
25/5 = 5.
3 x 5 / 5+5+5 = 15
15/25 = 3/5
Solve. 6 Everyone at a park was either hiking or riding a bike. There were 24 more hikers than bike riders. If there were a total of 100 people at the park, how many were hiking?
b r = 178 + h;
b r + h = 676;
then, 178 + 2h = 676 => h = 498/2 = 249 => b r = 178 + 249 = 427
Answer:
676
Step-by-step explanation:
h=b+178=427
b=b=249
-------------
(b+178)+b=676
2b+178=676
2b=498
b=249
-------------
249+427=676
Kaneppeleqw and 2 more u
Help help help math math help
x = 27
Step-by-step explanation:
The two angles shown are called co-exterior angles and by definition, their sum is equal to 180° so we can write
[tex](3x - 3) + (4x - 6) = 180[/tex]
[tex]\Rightarrow 7x - 9 = 180[/tex]
Simplifying this further, we get
[tex]7x = 189 \Rightarrow x = 27[/tex]