Question

9) Solve by the elimination method.

x + y = -5
x - y = 11

Answer 1

x = 3

y = -8

Explanation:

x + y = -5

x - y = 11

Since the y's will cancel out, we don't need to modify the two equations in any way.

Now, just add the two equations.

x + x = 2x

y + (-y) = 0

-5 + 11 = 6

2x = 6

Divide by 2.

x = 3

To find y, plug 3 in as "x" in one of the two equations.

3 + y = -5

y = -8