SOLUTION: 2x+y=7 2x-2y=-8 Could someone please help me?

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Question 120848: 2x+y=7
2x-2y=-8
Could someone please help me?
Found 3 solutions by checkley71, Dailey27, Fombitz:
Answer by checkley71(8403) About Me  (Show Source):
You can put this solution on YOUR website!
2x+y=7
2x-2y=-8 now subtract these equations
-------------------------------
3y=15
y=15/3
y=5 answer
2x+5=7
2x=7-5
2x=2
x=2/2
x=1 answer.
proof
2*1-2*5=-8
2-10=-8
-8=-8
+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+10%2C+y+=+-2x+%2B7%2C+y+=+x+%2B4%29+ (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions y = -2x +7 and y = x +4).

Answer by Dailey27(1) About Me  (Show Source):
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1. 2x%2By=7
2. 2x-2y=-8
Use equation 1 to get 2x in terms of y and then substitute into equation 2.
2x%2By=7
2x=7-y
2. 2x-2y=-8
%287-y%29-2y=-8
7-3y=-8
-3y=-15
highlight%28y=5%29
Then from 1,
2x%2By=7
2x%2B5=7
2x=2
highlight%28x=1%29
Check your answers.
1. 2x%2By=7
2%281%29%2B5=7
2%2B5=7
7=7
True statement.
2. 2x-2y=-8
2%281%29-2%285%29=-8
2-10=-8
-8=-8
True statement.
Your answers led to true statements.
They are good answers.