Question

Solve the system using elimination.

3x + 3y = –9
3x – 3y = 21

Answer 1

add the two equation, the y variable will be eliminated

Answer 2

then solve for x

Answer 3

once you get what x is, you can replace it into one of the original equation to get y

Answer 4

can you give me an example

Answer 5

3x + 3y = –9 (1)
3x – 3y = 21 (2)
So: (1) + (2) => 6x=12=>x=2=>y=-5. So (2,-5) is right