Question

How do you solve this ? Please show work.

Answer 1

Solve for the first value in one of the equations, then substitute the result into the other equation.
(4,8)

Answer 2

3x + y = 20
x + y = 12

Subtract the bottom equation from the top one and get:

2x = 8

Divide both sides of the equation by 2 and get x = 4

Solve for y by substituting 4 in

x + y = 12 which is:

4 + y = 12

Subtract 4 from both sides of the equation and get y = 8.

The answer is x = 4, y = 8

or (4,8)