SOLUTION: 3x-5y=7 -9x+15y=-21 solve for x and y

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Question 105803: 3x-5y=7
-9x+15y=-21
solve for x and y
Answer by checkley75(3666) About Me  (Show Source):
You can put this solution on YOUR website!
3X-5Y=7
-5Y=-3X+7
Y=-3X/-5+7/-5
Y=3X/5-7/5 (RED LINE)
-9X+15Y=-21
15Y=9X-21
Y=9X/15-21/15
Y=3X/5-7/5 (GREEN LINE)
THESE TWO EQUATIONS ARE IDENTICAL THEREFORE THERE IS NO UNIQUE SOLUTION.
+graph%28+300%2C+200%2C+-6%2C+5%2C+-10%2C+10%2C+y+=+3x%2F5+-7%2F5%2C+y+=+3x%2F5+-7%2F5%29+ (graph 300x200 pixels, x from -6 to 5, y from -10 to 10, of TWO functions y = 3x/5 - 7/5 and y = 3x/5 -7/5).