SOLUTION: how do i solve 6x – 4y = 54 –9x + 2y = –69 with the substituteion method?

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Question 553050: how do i solve
6x – 4y = 54
–9x + 2y = –69
with the substituteion method?
Answer by TutorDelphia(193) About Me  (Show Source):
You can put this solution on YOUR website!
This is set up better to do the elimination method, but lets do substitution
Lets solve 6x – 4y = 54 for y
6x – 4y = 54
subtract 6x from both sides
-4y=-6x+54
divide everything by -4
y=1.5x-13.5
Now we can sub in for y using the other equation
–9x + 2(1.5x-13.5) = –69
-9x+3x-17=-69
-6x-17=-69
-6x=-52
x=52/6
Sub in 52/6 for x in the other equation
6x – 4y = 54
6*(52/6)-4y=54
52-4y=54
-4y=2
y=-(1/2)
x=52/6=26/3=8 2/3