Question

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

Answer 1

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 )

Answer 2

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)