SOLUTION: 2x + 8y = 80 -2x + 2y = 0

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Question 491998: 2x + 8y = 80
-2x + 2y = 0
Found 2 solutions by ptth176, deborabr:
Answer by ptth176(50) About Me  (Show Source):
You can put this solution on YOUR website!
2x + 8y = 80(1)
-2x + 2y = 0 (2)
(1)+(2)=> 10y=80
=> y=8
(1)=>2x+8x8=80
=>2x+64=80
=>2x=16
=>x=8
Finally: x=8;y=8

Answer by deborabr(181) About Me  (Show Source):
You can put this solution on YOUR website!
suming the two equations
2x + 8y = 80
-2x + 2y = 0
______________
0x + 10y = 80
y = 80/10
y = 8
substituting y to find x
-2x + 2*8 = 0
-2x + 16 = 0
-2x = -16 multiplying by -1 to change the signal
2x = 16
x = 16/2
x = 8