SOLUTION: how do it find the intersection of the lines x subscript 1 -5x subscript 2 =1 and 3x subscript 1 -7xsupscript 2 =5

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Question 259757: how do it find the intersection of the lines x subscript 1 -5x subscript 2 =1 and 3x subscript 1 -7xsupscript 2 =5
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
Instead of subscript 1 and 2, let's do this
x1=x
x2=y
It'll reduce the confusion, I think.
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1.x-5y=1
2.3x-7y=5
Use eq. 1 to solve for x in terms of y.
x=1%2B5y
Now substitute into eq. 2 and solve for y.
3x-7y=5
3%281%2B5y%29-7y=5
3%2B15y-7y=5
8y=2
y=1%2F4
Then use eq. 1 again,
x=1%2B5y
x=1%2B5%281%2F4%29
x=9%2F4
Now we can re-name them back to the originals,
x1=9%2F4
x2=1%2F4