SOLUTION: solve each system using the substitution method. 5x-8y=-17 and 3x-y=5

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Question 176082: solve each system using the substitution method. 5x-8y=-17 and 3x-y=5
Answer by EMStelley(208) About Me  (Show Source):
You can put this solution on YOUR website!
5x-8y=-17
3x-y=5
In order to use the substitution method, we must use one of the equations to solve for one of the variables. It appears that the second equation would be the easiest, solving for y. If you add y to both sides and subtract 5 from both sides, you get:
y=3x-5
Using this, we replace y in the first equation with 3x-5:
5x-8%283x-5%29=-17
5x-24x%2B40=-17
-19x%2B40=-17
-19x=-57
x=3
To find y, you plug in x=3 to either equation. I will use the second one.
3%283%29-y=5
9-y=5
y=4
So the solution is (3,4).