SOLUTION: . Solve by substitution or elimination method: -4x + 3y = 5 12x - 9y = -15

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Question 164199: . Solve by substitution or elimination method:
-4x + 3y = 5
12x - 9y = -15
Answer by Fombitz(32388) About Me  (Show Source):
You can put this solution on YOUR website!
1.-4x+%2B+3y+=+5
2.12x+-+9y+=+-15
Multiply eq. 1 by 3 and add to eq. 2,
3%28-4x%2B3y%29%2B%2812x-9y%29=15%2B%28-15%29
-12x%2B9y%2B12x-9y=0
0=0
That's true.
Eq. 1 and 2 are dependent.
They are the same equation and have infintely many solutions.