SOLUTION: Solve the following systems by substitution. 5x - 2y = -5 y - 5x = 3

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Question 71012: Solve the following systems by substitution.
5x - 2y = -5
y - 5x = 3

Answer by elima(1433) About Me  (Show Source):
You can put this solution on YOUR website!
5x - 2y = -5
y - 5x = 3
First you need to solve one of the equations for either x or y, since y is already by itself in the second equation llets solve that one for y;
y-5x=3
add -5x to both sides;
y=3+5x
Now but this equation in place of the y in the first equation;
5x - 2(3+5x)=-5
distribute the 2;
5x-6-10x=-5
-6-5x=-5
add 6 to both sides;
-5x=-5+6
-5x=1
divide each side by -5;
-5x%2F-5=1%2F-5
x=-1%2F5
now plug that in for x in either equation, we will go ahead and usethe first again;
5(-1%2F5) - 2y = -5
-5%2F5-2y=-5
-1-2y=-5
add 1 to both sides;
-1-2y+1=-5+1
-2y=-4
divide each side by -2
y=-4%2F-2
y=2
so you have;
x=-1%2F5
y=2
:)