SOLUTION: solve by substitution method 5x+8y=5 3x-8y=-61

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Question 469800: solve by substitution method
5x+8y=5
3x-8y=-61
Answer by Tatiana_Stebko(1539) About Me  (Show Source):
You can put this solution on YOUR website!
system%285x%2B8y=5%2C3x-8y=-61%29
From the first equation 8y=5-5x substitute into the second equation
system%288y=5-5x%2C3x-%285-5x%29=-61%29
3x-5%2B5x=-61
8x=-61%2B5
8x=-56
x=-56%2F8
x=-7
Substitute x=-7 into the first equation
8y=5-5%2A%28-7%29
8y=40
y=40%2F8
y=5
Answer: (-7,5)
Check
system%285%2A%28-7%29%2B8%2A5=5%2C3%2A%28-7%29-8%2A5=-61%29
system%285=5%2C-61=-61%29-correct