SOLUTION: 4x + 5y = 51 4x

SOLUTION: 4x + 5y = 51 4x - 5y = 21

Question 238492: 4x + 5y = 51
4x - 5y = 21
Answer by Fombitz(32388) (Show Source): You can put this solution on YOUR website!
Add the equations together.
4x+5y+4x-5y=51+21
8x=72
x=9
THen use either equation to solve for y.
4x+5y=51
4(9)+5y=51
36+5y=51
5y=15
y=3
(x,y)=(9,3)
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