SOLUTION: substitution on linear equations. 4x-5y=20 and 5x+5y=70

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Question 314756: substitution on linear equations.
4x-5y=20 and 5x+5y=70
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.4x-5y=20
2.5x%2B5y=70
From eq. 2,
5y=70-5x
Substitute into eq. 1,
4x-%2870-5x%29=20
4x-70%2B5x=20
9x=90
highlight%28+x=10%29
Then,
5y=70-5x
5y=70-50
5y=20
highlight%28y=4%29