Question

A system of equations is given.

3y = 20 − 4x
2y = 12 − 3x

Solve for (x, y) using the elimination method. Show all work

Answer 1

The solution is (-4, 12).

Explanation:

3y = 20 − 4x

2y = 12 − 3x

Multiply the first equation by 2 and the second by 3:

6y = 40 - 8x

6y = 36 - 9x

Subtracting:

0 = 4 -8x - (-9x)

0 = 4 + x

x = -4.

Now substitute x = -4 in the first equation:

3y = 20 - 4(-4)

3y = 20 + 16

3y = 36

y = 12.