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2 years ago

Solve the system of linear equations by elimination. -3.x – 5y = -7 -4x + 5y = 14

Mathematics

2 answers:

julia-pushkina [17]2 years ago

8 0

Answer:

(- 1, 2 )

Step-by-step explanation:

Given the 2 equations

- 3x - 5y = - 7 → (1)

- 4x + 5y = 14 → (2)

Add the 2 equations term by term to eliminate y , that is

- 7x + 0 = 7

- 7x = 7 ( divide both sides by - 7 )

x = - 1

Substitute x = - 1 into either of the 2 equations and solve for y

Substituting into (1)

- 3(- 1) - 5y = - 7

3 - 5y = - 7 ( subtract 3 from both sides )

- 5y = - 10 ( divide both sides by - 5 )

y = 2

solution is (- 1, 2 )

xxTIMURxx [149]2 years ago

4 0

Answer:

( -1, 2)

Step-by-step explanation:

Since this is asking for elimination, you will need to line up x or y to be the opposite amount:

-3x -5y = -7

-4x + 5y = 14

(notice -5y and 5y are already opposite, therefore no further actions are needed to line them up.)

Next step is to add both equations up to eliminate y and to find x:

-7x = 7

x = -1

After finding x, plug the x back into either one of the equations to solve for y. If you are unsure, you can plug it into the other equations to double check.

If you chose to do equation 1:

-3(-1) -5y = -7

3 -5y = -7

-5y = -10

y = 2

If you chose to do equation 2:

-4(-1) + 5y = 14

4 + 5y = 14

5y = 10

y = 2

After finding x and y, you will find the point ( -1, 2)

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Aloiza [94]

5(p+5) + 6(p+6)

First step: Distribute (PEMDAS --> Parenthesis)

5p + 25 + 6p + 36 Now, combine like terms

11p + 61

Thus, the answer is 11p + 61

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2 years ago

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I can't figure out how to do this problem.

Marianna [84]

Have you tried multiplying 5(3)+2(2)+1?

15 + 4 + 1 = 20 ?

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5 0

3 years ago

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16 OT 26

hram777 [196]

Answer:

$Total = 166cm^2$

Step-by-step explanation:

Given

See attachment

Required

Determine the surface area

The figure is made up of two cuboids and the surface area of a cuboid is:

$Area = 2LB + 2LH + 2BH$

Because the bottom part of the upper piece is not visible, the area is calculated as:

$Area = 2LB + 2LH + BH$

This gives:

$Area = 2 * 5*4 + 2 * 4 * 2 + 5 * 2$

$Area = 66$

For the bottom piece:

We calculate its area as $Area = 2LB + 2LH + 2BH$ . However, the area of the invisible part will be subtracted.

So, we have:

$Area = 2*3*5 + 2*3*5 + 2*5*5 - 2*5$

$Area = 100$

The total surface area is:

$Total = 66 + 100$

$Total = 166cm^2$

5 0

3 years ago

Use the ordinary division of polynomials to find the quotient and remainder when the first polynomial is divided by the second.

Vanyuwa [196]

The quotient and remainder when the first polynomial is divided by the second are -4w^2 - 7w - 21 and -71 respectively

<h3>How to determine the quotient and remainder when the first polynomial is divided by the second?</h3>

The polynomials are given as:

-4w^3 + 5w^2 - 8, w - 3

Set the divisor to 0.

So, we have

w - 3 = 0

Add 3 to both sides

w = 3

Substitute w = 3 in -4w^3 + 5w^2 - 8 to determine the remainder

-4(3)^3 + 5(3)^2 - 8

Evaluate the expression

-71

This means that the remainder when -4w^3 + 5w^2 - 8 is divided by w - 3 is -71

The quotient (Q) is calculated as follows:

Q = [-4w^3 + 5w^2 - 8]/[w - 3]

The numerator can be expressed as follows:

Numerator = -4w^3 + 5w^2 - 8

Subtract the remainder.

So, we have:

Numerator = -4w^3 + 5w^2 - 8 + 71

This gives

Numerator = -4w^3 + 5w^2 + 61

So, the quotient becomes

Q = [-4w^3 + 5w^2 + 61]/[w - 3]

Expand

Q = [(w - 3)(-4w^2 - 7w - 21)]/[w - 3]

Evaluate

Q = -4w^2 - 7w - 21

Hence, the quotient and remainder when the first polynomial is divided by the second are -4w^2 - 7w - 21 and -71 respectively