SOLUTION: solve systems of equations of numbers 1 to 10 by the addition or substraction 3x+2y=5 9x-2y=15

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Question 135228: solve systems of equations of numbers 1 to 10 by the addition or substraction
3x+2y=5
9x-2y=15
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Solve by addition/subtraction:
1) 3x%2B2y++=+5
2) 9x-2y+=+15 Add equation 1) to equation 2)
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3) 12x+=+20 Divide both sides by 12.
3a) x+=+20%2F12 Simplify.
x+=+5%2F3 Now substitute this for x in equation 1).
3%285%2F3%29%2B2y+=+5
5%2B2y+=+5 Subtract 5 from both sides.
2y+=+0 Divide both sides by 2.
y+=+0
The solution is: (5%2F3,0)