SOLUTION: solve. system by substitution y=-4x-7 y=3x

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Question 238650: solve. system by substitution
y=-4x-7
y=3x
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 first equation to find y.
.
Problem:
y=-4x-7
y=3x
.
3x=-4x-7
7x=-7
x=-%287%2F7%29
x=-1
.
y=-4x-7
y=-4%28-1%29-7
y=4-7
y=-3
.
Your answers are x=-1 and y=-3