SOLUTION: how do i find the solution using substitution to: 15x-10y=-1 15y=-2+5x

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Question 268214: how do i find the solution using substitution to:
15x-10y=-1
15y=-2+5x
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
15x - 10y =-1
15y = -2 + 5x
:
Use the 2nd equation for substitution
Rearrange to
5x = 15y + 2
divide by 5
x = (3y + .4)
:
Substitute (3y+.4) for x in the 1st equation
15(3y + .4) - 10y = -1
45y + 6 - 10y = -1
45y - 10y = -1 -6
35y = -7
y = %28-7%29%2F35
y = -.2
;
Find x:
x = 3y + .4
x = 3(-.2) + .4
x = -.6 + .4
x = -.2
:
:
Check solution in the 1st equation
15(-.2) - 10(-.2) =-1
-3 + 2 = -1