SOLUTION: what is x and y for 5x+4y=73 and -4x+4y=-8

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Question 385860: what is x and y for 5x+4y=73 and -4x+4y=-8
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
Multiply the 2nd equation by -1: 4x - 4y = 8.
Add this result with the first equation to get 9x = 81, or x = 9.
Then using the 1st equation, 5*9 + 4y = 73, or 4y = 28, or y = 7.