SOLUTION: solve x+y=13 and x*y=40.find x and y

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Question 388023: solve x+y=13 and x*y=40.find x and y
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.x%2By=13
2.xy=40
From eq. 1,
x=13-y
Substitute into eq. 2,
%2813-y%29y=40
13y-y%5E2=40
y%5E2-13y%2B40=0
%28y-5%29%28y-8%29=0
Two solutions:
y-5=0
y=5
Then from eq. 2,
x%285%29=40
x=8
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y-8=0
y=8
x%288%29=40
x=5
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