SOLUTION: I have to solve by substitution. Clear fractions first. 1/5x+1/5y=1 1/5x-1/5y=9/5 I keep getting the wrong answer.

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Question 449108: I have to solve by substitution. Clear fractions first.
1/5x+1/5y=1
1/5x-1/5y=9/5
I keep getting the wrong answer.
Answer by Leaf W.(135) About Me  (Show Source):
You can put this solution on YOUR website!
1. %281%2F5%29x+%2B+%281%2F5%29y+=+1
2. %281%2F5%29x+-+%281%2F5%29y+=+9%2F5
==> Clear fractions by multiplying all elements by 5 (the LCD):
1. %285%29%281%2F5%29x+%2B+%285%29%281%2F5%29y+=+%285%29%281%29
2. %285%29%281%2F5%29x+-+%285%29%281%2F5%29y+=+%285%29%289%2F5%29
==> Simplify. Notice that (5) cancels out (/5):
1. x+%2B+y+=+5
2. x+-+y+=+9
==> Since you want to solve by substitution, you must isolate any variable in either of the equations. I am going to isolate the x in the second equation by adding y to both sides.
2. x+=+y+%2B+9
==> Substitute this value (y + 9) for x into the first equation.
1. y+%2B+9+%2B+y+=+5
==> Add like terms:
1. 2y+%2B+9+=+5
==> Subtract 9 from both sides:
1. 2y+=+-4
==> Divide both sides by 2:
1. y+=+-2
==> So, your y-coordinate is -2. Next, solve for x by plugging this value of y into the equation for x found a few steps ago (x = y + 9):
x+=+-2+%2B+9
==> Add like terms:
x+=+7
==> So, x-coordinate is 7. Plug these values for x and y into coordinate form (x, y): (7, -2)
***Therefore, your answer is (7, -2)