Question

Describe the steps necessary to solve the following system equations:

-3x - 4y = 2 and 3x + 3y = -3

Answer 1

x = -2 and y = 1

Explanation:

3x + 3y = -3, x + y = -1, x = -y -1

-3(-y-1) - 4y = 2, 3y + 3 - 4y - 2 = 0

-y +1 = 0, y = 1

x + y = -1, x + 1 = -1, x = -2

Answer 2

(- 2, 1 )

Explanation:

Given the 2 equations

- 3x - 4y = 2 → (1)

3x + 3y = - 3 → (2)

Adding the 2 equations term by term will eliminate the x- term, that is

0 - y = - 1

- y = - 1 ( multiply both sides by - 1 )

y = 1

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

Substituting into (2)

3x + 3(1) = - 3

3x + 3 = - 3 ( subtract 3 from both sides )

3x = - 6 ( divide both sides by 3 )

x = - 2

solution is (- 2, 1 )