SOLUTION: Substitution method 6x+2y-4=0 and 10x+7y= -8

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Question 238526: Substitution method
6x+2y-4=0 and 10x+7y= -8
Answer by College Student(505) About Me  (Show Source):
You can put this solution on YOUR website!
To solve by substitution:
1. Leave first equation alone for now.
2. Solve for y on the second equation.
3. Plug in this value into the first eqn to find x
4. Once you know the x value, plug it again in the forst equation to find y.
.
Problem:
6x%2B2y-4=0
10x%2B7y=-8
.
10x%2B7y=-8
7y=-8-10x
y=%28-8-10x%29%2F7
.
6x%2B2%28%28-8-10x%29%2F7%29-4=0
6x%2B%28%28-16-20x%29%2F7%29-4=0 ... now multiply by 7 to get rid of fraction
7%2A6x%2B7%2A%28%28-16-20x%29%2F7%29-4%2A7=0
42x-16-20x-28=0 ... now combine like terms
22x=16%2B28
x=44%2F22
x=2
.
6x%2B2y-4=0
6%282%29%2B2y-4=0
12%2B2y-4=0
2y=-8
y=-%288%2F2%29
y=-4
.
Here are your answers: x=2 and y=-4