SOLUTION: 3x-y=7 10x-5y=25 solve by elimination,substitution,& graphing

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Question 130889: 3x-y=7 10x-5y=25 solve by elimination,substitution,& graphing
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.3x-y=7
2.10x-5y=25
Multiply eq. 1 by (-5) and add the equations together to eliminate y and solve for x.
-15x%2B5y%2B10x-5y=-35%2B25
-5x=-10
x=2
Then use either equation to solve for y.
3%282%29-y=7
6-y=7
y=-1
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.
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1.3x-y=7
2.10x-5y=25
From eq. 1,
y=3x-7
Substitute into eq. 2,
10x-5%283x-7%29=25
10x-15x%2B35=25
-5x=-10
x=2
Then,
y=3%282%29-7
y=-1
.
.
.