SOLUTION: Solve each of the following systems by substitution 5x - 2y = -5 y - 5x = 3 Please help, I understand the addition method but not the substitution

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Question 120966: Solve each of the following systems by substitution
5x - 2y = -5
y - 5x = 3
Please help, I understand the addition method but not the substitution
Answer by nabla(475) About Me  (Show Source):
You can put this solution on YOUR website!
Solve the first equation for y:
y=%285%2F2%29x%2B5%2F2
Substitute this into the second equation for y:
%285%2F2%29x%2B5%2F2-5x=3
Solve:
%28-5%2F2%29x=1%2F2
x=-1%2F5
Substitute this x into the first equation we found:
y=%285%2F2%29%28-1%2F5%29%2B5%2F2=-1%2F2%2B5%2F2=2
Which gives solution set S={(-1/5,2)}
I will leave the check up to you.
In sum:
1) Solve one of the equations for a variable, generally y.
2) Plug the y gotten in step 1 into the other equation.
3) Solve for the other variable in this new equation (generally x).
4) Plug the value of x into the equation gotten in step 1 for the value of y.
5. Check