SOLUTION: solving linear systems using substitution, what is 4x-7y=10 y=x-7

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Question 423206: solving linear systems using substitution, what is
4x-7y=10
y=x-7
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
4x-7y=10 .............1
x-y=7.............2

multiply (1)by -1
Multiply (2) by 7
-4x+7y=-10
7x-7y=49

Add the two equations

3x=39

/3

x=13

plug value of x in (1)

4x-7y=10
52-7y=10
-7y=10-52
-7y=-42
y=6