SOLUTION: Not sure what category this would fit under...... My assignment is on substitution....I did the problems but not sure if they are right...(I was able to do the other problems on

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Question 238328: Not sure what category this would fit under......
My assignment is on substitution....I did the problems but not sure if they are right...(I was able to do the other problems on the sheet but none of them had fractions or three different variables)- can someone post the proper steps to solve the problems (so I can check it against what I have...)?
1) 6x+2y-4=0 and 10x+7y= -8
2) 2/3x+y= -5/3 and x-1/3y= -13/3
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.
.
Since you've already done the problems, I'm only posting one so you can verify the steps and results.
.
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