Solve systems by elimination step by step
2x + y = 180
x - y = 30

Answers

Answer 1

The value of x=70 and y=40

The elimination method is the process of eliminating one of the variables in the system of linear equations using the addition or subtraction methods in conjunction with the multiplication or division of coefficients of the variables.

Here, 2x+y=180

x-y= 30

Here, the coefficient of y in these two equations are equal and have opposite signs. so,

                             2x+y= 180

                             x-y= 30

     Now adding equation 1 and equation 2

We get,

               3x= 210

                  x= 210/3

                  x= 70

Now, to find y:

Putting the value of x in equation 2

          x-y= 30

         70-y= 30

          y= 70-30

           y= 40

so, the value of x and y are 70 and 40

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Related Questions

hey any help? (please make sure this is correct i'd appreciate it)

Answers

Answer:

Below

Step-by-step explanation:

Line AB is of the form y = mx + b    where m is the slope = 2

 Line BC is perpendicular to this and will have slope - 1/m = - 1/2   and includes the point C (0,6)

 The point slope form of line BC will then be

     ( y-6) = - 1/2 ( x - 0)    which can be re-arranged to

       y = - 1/2x + 6     < ==== equation for line BC

       

Write an addition equation with three equal fractional parts.
15
4
=
+
+

Answers

Step-by-step explanation:

please refer to the sketch

find the mean in the picture

Answers

Hey I think it’s 20 just did it in my head

An item on sale costs 80% of the original price. The original price was 33%

Answers

The sale price of the item is given by the equation A = $ 26.40

What is an Equation?

Equations are mathematical statements with two algebraic expressions flanking the equals (=) sign on either side.

It demonstrates the equality of the relationship between the expressions printed on the left and right sides.

Coefficients, variables, operators, constants, terms, expressions, and the equal to sign are some of the components of an equation. The "=" sign and terms on both sides must always be present when writing an equation.

Given data ,

Let the sale price of the item be represented as A

Now , the equation will be

The original price of the item = $ 33

An item on sale costs 80% of the original price

So , the sale price of the item A = 80 % x original price of the item

Substituting the values in the equation , we get

The sale price of the item A = ( 80 / 100 ) x 33

The sale price of the item A = 0.80 x 33

The sale price of the item A = $ 26.40

Therefore , the value of A is $ 26.40

Hence , the sale price is $ 26.40

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The diagonals of a quadrilateral ABCD intersects each other at the point O such that AO/BO=CO/DO.Prove that ABCD is a trapezium.​

Answers

Answer:

Step-by-step explanation:

To prove that a quadrilateral ABCD is a trapezium when the diagonals intersect at a point O such that AO/BO=CO/DO, we can use the fact that opposite sides of a trapezium are parallel.

First, let's draw a diagram to represent the given information:

[asy]

pair A, B, C, D, O;

A = (0,0);

B = (2,0);

C = (3,2);

D = (1,2);

O = intersection point(A-C, B--D);

draw(A--B--C--D--cycle);

draw(A-C);

draw(B--D);

label("A", A, W);

label("B", B, E);

label("C", C, E);

label("D", D, W);

label("O", O, N);

label("$\theta_1$", (B+O)/2, NE);

label("$\theta_2$", (O+D)/2, NE);

label("$\theta_3$", (O+C)/2, NW);

label("$\theta_4$", (A+O)/2, NW);

[/asy]

Since the diagonals intersect at point O, the angles formed by the diagonals at O are supplementary (that is, they add up to 180 degrees). In other words, we have:

θ1 + θ2 = 180 degrees

θ3 + θ4 = 180 degrees

Since AO/BO=CO/DO, the triangles AOB and COD are similar. This means that the ratios of their sides are equal. We can write this as:

AO/BO = CO/DO

We can also write this as:

AO/DO = CO/BO

Then, since the angles formed by the diagonals at O are supplementary, we have:

θ1 + θ2 = 180 degrees

θ1 + θ4 = 180 degrees

Subtracting these two equations gives us:

θ2 - θ4 = 0

Since the angles are equal, they are also opposite angles of the quadrilateral ABCD. Therefore, the opposite sides of AB and CD are parallel, which means that ABCD is a trapezium.

The weight of the square is 10 grams. How much heavier is the circle than the square?

Answers

By adding the weight of the triangle, the weight of the circle heavier than that of the square.

How to determine how much heavier the circle is than the square

The linear equation that results from examining the weights will contain the following parameters.

Let t stand for the triangle.

Let c stand for the circle.

Let's use the shape square.

left side of the equation = 6s + 3t

right side of the equation = 3s + 3c

equating both sides

6s + 3t = 3s + 3c

6s - 3s + 3t = 3s + 3c

3s + 3t = 3c

3(s + t) = 3c

dividing all through by 3

s + t = c

10 + t = c

Because of the resulting equation, we can conclude that the the circle is weightier than the square by the weight of the triangle

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value of y please help me

Answers

Answer is y= 22

Step by step

We know the triangle dum is equal to 180

One angle is 40, so 180 - 40 = 140

The two angles labeled x are congruent, so 140 / 2 = 70.

X = 70

Now the supplement angle of x and 5y = 180 degrees.

70 + 5y = 180

Subtract 70 from both sides to isolate y

70 - 70 + 5y = 180 - 70
Simplify

5y = 110

Divide both sides by 5 to solve for y

5/5 y = 110/5

y = 22

1) A publisher wants to determine the thickness of a book they will print soon. The book has a front cover and a back cover, each of which have a thickness of

1/4 in. The publisher can choose on what type of paper to print the book.

Bond paper has a thickness of 1/4 in. per 100 pages.

Write an equation that gives the width `y` of the book, if it has `x`-hundred pages printed on bond paper.


Ledger paper has a thickness of 2/5 in. per `100` pages. Write an equation that gives the width `y` of the book, if it has `x`-hundred pages printed on ledger paper.

2) If the publisher selects front and back covers with a thickness of 1/3 in. each, how would this change the equations you wrote on the previous slides?

Answers

1a) An equation that gives the width `y` of the book, if it has `x`-hundred pages printed on bond paper is; y = ¹/₂ + ¹/₄x

1b) Ledger paper has a thickness of 2/5 in. per `100` pages, the equation is; y = ¹/₂ + ²/₅x

2) The equation will be; y = ²/₃ +¹/₄x

How to solve Algebraic Word Problems?

1) We are told that the front cover and the back cover have a thickness of 1/4 inches and they also have a thickness of 1/4 inch. Thus;

The addition of both gives to the book thickness of;

1/4 + 1/4 = 1/2 inch, despite how many pages the book  has.

We are told that for every hundred pages, a thickness of 1/4 inch is added to the book, then the equation is:

y = ¹/₂ + ¹/₄x

where;

y is the width of the book in inches.

x is every hundred pages printed on bond paper.

1b) If ledger paper has a thickness of 2/5 in. per 100 pages, then the equation is now;

y = ¹/₂ + ²/₅x

2) If both front and back covers now, have a thickness of 1/3 inches instead of 1/4 inches each, then the equation will be;

y = 2(1/3) +¹/₄x

y = ²/₃ +¹/₄x

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a tee junction occurs when a connection meets an existing pipe of header at what angle? A 180 degree, B 30 degree, C. 90 degree, D.45 degree

Answers

Tee welding joints are formed when two members intersect at a 90-degree angle that makes the edges come together in the center of a plate or component

Select the correct answer. What is this equation rewritten in exponential form? log7 343 = 3 A. 37 = 343 B. 73 = 343 C. 343x = 7 D. 343x = 3

Answers

The solution to the equation log₇343 = 3 is 7³ = 343

What is an equation?

An equation is used to show the relationship between numbers and variables.

The logarithm can be defined as the exponent that raises a base to get a particular number. The law of logarithm states:

logₓm = n is the same as xⁿ = m

Given the equation:

log₇343 = 3

Applying the law of logarithm gives:

7³ = 343

The solution to the equation is 7³ = 343

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Please help me with this question

Answers

Answer:

Step-by-step explanation:

i have no idea

Customary American Units of Capacity

1 cup = 8 ounces

1 pint = 2 cups or 16 ounces

1 quart = 2 pints, 4 cups, or 32 ounces

1 gallon = 4 quarts, 8 pints, 16 cups, or 128 ounces

5 quarts 4 pints =____ pints

Answers

Answer:

14

Step-by-step explanation:

5 quarts = 10 pints

10 pints + 4 pints = 14 pints

evaluate - [tex]6^{2}- 2(5+1+3[/tex]

Answers

The expression 6² - 2(5 + 1 + 3) after evaluation gives 18.

What is BODMAS rule?

BODMAS rule is rule for operation of numbers in a specific order when more than one type of operations is involved.

BODMAS is the abbreviated form for Brackets, Order including powers and exponents, Division, Multiplication, Addition and Subtraction.

Given expression is, 6² - 2(5 + 1 + 3).

First we should do the operation in brackets.

6² - 2(5 + 1 + 3) = 6² - 2 (9)

Now we should do the power operations.

6² - 2 (9) = 36 - 2 × 9

Now we do multiplication.

36 - 2 × 9 = 36 - 18

Now we do subtraction.

36 - 18 = 18

Hence the answer of the expression given is 18.

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If m∠ABJ = 28, ∠ABC ≅ ∠DBJ, find m∠JBC.

Answers

Answer:

Step-by-step explanation:

If m∠ABJ = 28 and ∠ABC ≅ ∠DBJ, then we can set up the following equation:

m∠ABC = m∠DBJ

Since angles ∠ABC and ∠DBJ are congruent, they have the same measure, so the equation above is true.

Since we are trying to find m∠JBC, we can use the fact that the measure of an angle is equal to the sum of the measures of the other two angles in the triangle to set up another equation:

m∠JBC = m∠ABC + m∠ABJ

Substituting the value for m∠ABC from the first equation into the second equation, we get:

m∠JBC = m∠DBJ + m∠ABJ

Substituting the given value of m∠ABJ into this equation, we get:

m∠JBC = m∠DBJ + 28

Since m∠ABJ = m∠DBJ, we can substitute m∠ABJ in for m∠DBJ:

m∠JBC = m∠ABJ + 28

Substituting the given value of m∠ABJ into this equation, we get:

m∠JBC = 28 + 28

Solving this equation, we find that m∠JBC = 56.

Therefore, the measure of angle ∠JBC is 56 degrees.

15. The center of the circle in the figure is at O. Determine the measure of ZABC.

Answers

According to the Central Angle Theorem, the central angle occupied by two points on a circle will always be twice the inscribed angle occupied by those same two points, therefore ∠ABC = 1/2 × 56 = 28°.

What is Central Angle Theorem?

Since subtended and inscribed angles are mentioned in the definition, we must first understand them in order to understand the central angle theorem. An object at a specific outer position forms an angle known as a subtended angle.

If you disagree with that definition, think about this: On Earth, you are standing and gazing up at the sun. A triangle with three sides is created. The sun's height, the sun ray that travels from the bottom of the sun to your eyes, and these three directions are the three sides of the sun.

The Central Angle Theorem states that the central angle occupied by two points on a circle is always twice the inscribed angle occupied by those same two points.

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5. Jackson purchased a pack of game cards that was on sale for 22% off. The sales tax in his county is 6%. Let y represent the original price of the cards. Write an expression that can be used to determine the final cost of the cards.

Answers

Answer:  0.8268y

The decimal value is exact without any rounding.

==========================================================

Explanation:

If Jackson saves 22%, then he pays the remaining 100% - 22% = 78%, which leads to the decimal value 0.78

An increase of 6% leads to 100%+6% = 106% and that converts to 1.06

Multiply those decimal values: 0.78*1.06 = 0.8268; this trick is useful to chain together multiple discounts and/or tax increases.

Therefore, the final cost expression is 0.8268y where the variable y is the original price before the discount and taxes.

---------

Extra info:

The expression 0.8268y tells us that Jackson is paying 82.68% of the original price. Note how 100% - 82.68% = 17.32%

This means Jackson is getting a real discount of 17.32% after the taxes have been considered.

Will mark brainliest (I also need to find the x and y intercepts)

Answers

Answer: downward, (4, -1), x = 4, no x-intercept, y-intercept: -6

Step-by-step explanation:
1. The parabla opens downwards because the y-values only decrease
2. The Vertex is the point with an x-value that creates a line of symmetry and can be noticed as it does not share the same x or y-value with any other point. If you look for it, you will notice that it's (4, -1).
3. As I explained above the x-value of the vertex creates a line of symmetry, therefore you can create the equation for the axis of symmetry by setting it equal to x.
4. X-intercepts are x-values that intersect with the x-axis so look for any points on the x-axis and if there are any, write them down. Y-intercepts are y-values that intersect with the y-axis, so look for any points on the y-axis and if there are any, write them down. If you checked, you should've realized that there are no x-intercepts and that the y-intercept is -6 and it's location is (0, -6).

All of the quadrilaterals in the shape below are squares. Find the area of the shaded
region.

Answers

Answer: I don't remember how to solve, but, I figured out the lengths of each side in the shaded region:

11, 11, 7, 7, 4, 4

Step-by-step explanation:

Hope this helps!! :D

Area of the shaded region is 105 units²

- Complete the function table for f(x) = 3x + 2.
groce
x
-2
-1
0
1
opies of graph pap

Answers

The value of the function f(x) at x = - 2, - 1, 0, 1 are - 4, - 1, 2, 5.

What is a function?

A function can be defined as the outputs for a given set of inputs.

The inputs of a function are known as the independent variable and the outputs of a function are known as the dependent variable.

Given, A function f(x) = 3x + 2.

Now,

At x = - 2, f(x) = 3(-2) + 2 ⇒ f(x) = - 4.

At x = - 1, f(x) = 3(-1) + 2 ⇒ f(x) = - 1.

At x = 0, f(x) = 3(0) + 2 ⇒ f(x) = 2.

At x = 1, f(x) = 3(1) + 2 ⇒ f(x) = 5.

This can also be written in the form of ordered pairs

(- 2, - 4), (- 1, - 1), (0, 2), (1, 5).

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A certain type of fertilizer contains 8% nitrogen. If 2 kilograms of nitrogen are needed to fertilize a lawn, how many kilograms of fertilizer are needed?

Answers

25 kilograms of fertilizer would be needed to fertilize the lawn.

what is the percentage?

In essence, percentages are fractions with 100 as the denominator. We place the percent symbol (%) next to the number to indicate that the number is a percentage.

given, A certain type of fertilizer contains 8 percent of nitrogen. If 2 kilograms of nitrogen are needed to fertilize a lawn.

Since fertilizer contain 8% nitrogen in it

thus for 80 grams of nitrogen = 1 kg of fertilizer

for 1 gram of nitrogen = 1/80 kg fertilizer

for 2000 gram of nitrogen = (1/80)* 2000 kg fertilizer

for 2 kilograms of nitrogen = 25 kg fertilizer

therefore, To fertilize the yard, 25 kg of fertilizer would be required.

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If the HCF is 5 and the product of the two numbers is 70, find the value of LCM.

Answers

If the HCF is 5 and the product of the two numbers is 70, then the value of LCM is 14.

Do two numbers make a product when they are the LCM of two numbers?

The smallest number that can be divided by both numbers is known as the least common multiple, or LCM, of two numbers. The product of the two numbers is the LCM if their greatest common divisor is 1, in which case their product is 1.

Using the fundamental theorem of mathematics, how do you find the HCF and LCM?

First, multiply both numbers by their prime factors to express them. Then, multiply the common factor with the highest power by the remaining factors to obtain the LCM. Take the common factors with the lowest power and multiply them to determine HCF.

To find the LCM of two numbers, you can use the formula: LCM = (a * b) / HCF.

In this case, we know that the HCF is 5, and the product of the two numbers is 70. Therefore, we can substitute these values into the formula:

LCM = (70) / 5 = 14.

So the LCM of the two numbers is 14.

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7 time a number , increased by 4




Answers

Answer:

7 times a number increased by 4 times the number

Let a number and the number be an arbitrary variable. Let's call it x. We have an algebraic expression. Let's take it in pieces:

7 times a number: 7x

4 times the number: 4x

The phrase increased by means we add 4x to 7x:

7x + 4x

Simplifying, we get: (7 + 4)x

11x

Step-by-step explanation:

Find the circumference of a circle with a diameter of 50 centimeters

Answers

Answer:

157.08 is the circumference. Hope it helps you

Step-by-step explanation:

PLEASE HELP ME 2 QUESTIONS ARE LISTED DOWN BELOW

Answers

A) The linear equation is:

y = (3/4)*x + 3

B) The sets with only positive elements are:

{x| x ∈ N}{y| 0 < y < 1}{y| 3 ≤ y ≤22}

How to write the linear equation?

A general linear equation can be written as:

y = a*x + b

Where a is the slope and b is the y-intercept.

Here, we do know that the y-intercept of the linear equation is (0, 3), then we know that b = 3.

Then the line is something like:

y = a*x + 3

We also know that the line passes through (-4, 0), then we can replace these values in the equation above to get:

0 = a*-4 + 3

4a = 3

a = 3/4

Then the linear equation is:

y = (3/4)*x + 3

In which sets all the numbers are positive?

The sets where all the numbers are positive are:

{x| x ∈ N}

Where N is the set of the natural numbers, these are all the integers equal to or larger than 1, so all are positives.

{y| 0 < y < 1}

There we can see that y must be larger than zero, so all the elements are positive.

{y| 3 ≤ y ≤22}

Here the elements are between 3 and 22, so all of these are positve.

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Find the area of a regular 12-sided polygon inscribed in a circle of radius
8 cm.

Answers

area of n sided polygon  inscribed in a circle is

A = (1/2)nr²sin(360/n)    (r = radius of circle)

A = (1/2)12*8²*sin30

   = 1/2*12*64*1/2

A  = 192  square unit

hello i need help with question 5 please

Answers

5a) The total cost of buying the car, including the harmonized sales tax (HST) of 13%, is $36,160.

5b) Under the lease, the customer saves $14,760.

5c) The lessee after returning the car has the following lease options:

Lease buyoutLease extensionNew lease contractBuying out the vehicle and then reselling it.

6a) The after-tax cost of the car that Jordan wants to buy is $32,199.35.

6b) The part of the Honda Civic that needs to be financed after the down payment is $26,199.35.

6c) The monthly payment will be $567.26.

6d) After four years, the total amount Jordan had paid for the vehicle is $33,228.48.

Car Financing Options:

A lease is a financing option for the use of capital assets by which the lessee utilizes an asset for a stated period while making periodic payments to the lessor.

A car purchase can also be financed through loans, like home mortgages.

Value of the car = $32,000

Harmonized Sales Tax (HST) = 13%

Cost of the car with HST = $36,160 ($32,000 x 1.13)

Lease Arrangement:

Down payment = $1,000

Financing part = $35,160 ($36,160 - $1,000)

Installment payments = 48

Periodic payments = $425

Total lease cost = $21,400 ($1,000 + 48 x $425)

Savings from leasing = $14,760 ($36,160 - $21,400)

Jordan's Car:

The value of the Honda Civic = $28,495

Harmonized Sales Tax (HST) = 13%

After-tax cost = $32,199.35 ($28,495 x 1.13)

Annual interest rate = 1.9% compounded monthly

Down payment = $6,000

Financing part = $26,199.35 ($32,199.35 -$6,000)

Financing period = 4 years

N (# of periods) = 48 months (4 years x 12)

I/Y (Interest per year) = 1.9%

PV (Present Value) = $26,199.35

FV (Future Value) = $0

P/Y (# of periods per year) = 12

C/Y (# of times interest compound per year) = 12

Results:

Monthly Payments (PMT) = $567.26

Sum of all periodic payments = $27,228.48

Total Interest $1,029.13

Total amount paid by Jordan after 4 years = $33,228.48 ($27,228.48 + $6,000)

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Mary is going for a walk. She takes 3 hours to walk 9.6 miles. What is her speed?

Answers

Answer:

3.2 mph

Step-by-step explanation:

If it takes her 3 hours to walk 9.6 miles, we need to divide 9.6 by 3.

To do so, we can remove the decimal point in 9.6, to give us 96.

Then, we can divide 96 by 3 to get 32.

Add the decimal back to 32.

Doing so would give us 3.2, and our answer.

We can check this answer by multiplying 3.2 by 3, which gives us 9.6, telling us our answer is correct.

Find the missing term 2,..,20,29

Answers

Answer:

11

Step-by-step explanation:

29-20= 91

2+9=11

11+9=

It would be 11, and the pattern is +9. 2+9 is 11, 11+9 is 20, 20+9 is 29

Find the midpoint of the line segment with endpoints:
(9, -5/2) to (-5, -3/2)
Answer must be as a point, using integers or reduced fractions for coordinates.

Answers

Answer:

Step-by-step explanation:

Midpoint formula is x3 = (x1+x2)/2, y3=(y1+y2)/2

so x3=(9-5)/2=2, y3=(-5/2-3/2)/2=-2.

the coordinates is (2, -2).

Katerina needs 200 balloons fillied with helium for a party. She knows that each balloon will need 0.7ft^3 of helium. the helium canisters hold 0.20m^3. 1m^3 = 35ft^3. How many Canisters will Katerina need to buy?

Answers

Answer:   20

=======================================================

Explanation:

1 balloon = 0.7 ft^3 of helium

200 balloons = 200*0.7 = 140 ft^3 of helium

Katerina needs 140 cubic feet of helium to fill all 200 balloons.

---------------

1m^3 = 35ft^3 which is approximate

0.2 m^3 = 0.2*35 = 7 ft^3

Each canister holds approximately 7 cubic feet of helium.

----------------

To summarize so far.

Katerina needs 140 cubic feet of helium.Each canister holds approximately 7 cubic feet of helium.

Let x be the number of canisters. Because of fact 2 mentioned above, 7x represents the total amount of helium from all of the x number of canisters.

Set this equal to the amount she needs (140) and solve for x.

7x = 140

x = 140/7

x = 20

Katerina needs 20 canisters.

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