SOLUTION: Please help me solve for the solution of the system equation 3y=4x+7 -4x-4y=28

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Question 522015: Please help me solve for the solution of the system equation
3y=4x+7
-4x-4y=28
Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
-4 x + 3 y = 7 .............1
-4 x -4 y = 28 .............2
Eliminate y
multiply (1)by 4
Multiply (2) by 3
-16 x 12 y = 28
-12 x -12 y = 84
Add the two equations
-28 x = 112
/ -28
x = -4
plug value of x in (1)
-4 x + 3 y = 7
16 + 3 y = 7
3 y = 7 -16
3 y = -9
y = -3