SOLUTION: x/2 - 9/x = -7/2

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Question 116066: x/2 - 9/x = -7/2
Answer by ankor@dixie-net.com(22740) About Me  (Show Source):
You can put this solution on YOUR website!
x%2F2 - 9%2Fx = -7%2F2
:
The common denominator would be 2x, right? If we multiply equation by 2x we can get rid of the denominators:
2x*x%2F2 - 2x*9%2Fx = 2x*-7%2F2
:
Cancel out the denominators and we have:
x(x) - 2(9) = x(-7)
:
x^2 - 18 = -7x
:
Arrange as a quadratic equation:
x^2 + 7x - 18 = 0
:
This factors to:
(x+9)(x-2) = 0
:
two solutions:
x = +2
and
x = -9
:
Check the x = -9 solution in the original equation:
%28-9%29%2F2 - 9%2F%28-9%29 = -7%2F2
Using a common denominator, minus a minus is a plus
-9%2F2 + 2%2F2 = -7%2F2
:
I'll let you check out the x=+2 solution