Answer:
(7,-2)
Step-by-step explanation:
You can solve this using the substitution method by:
x - y = 9
2x + y = 12
Let's take the first equation:
x - y = 9
Add y to both sides:
x = 9 + y
Then use this as a value in the other equation:
2 ( 9 + y ) + y = 12
Distribute and simplify:
18 + 2y + y = 12
18 + 3y = 12
Subtract 18 from both sides:
3y = -6
Divide each side by 3:
y=-2
Then use this value in one of the equations to get the other value:
x + y = 9
x + ( -2 ) = 9
Rearrange this to make it easier:
9 - 2 = x
7 = x
(7,-2) is your answer
Hope this helps!
