SOLUTION: Algebraically determine the EXACT roots in simplest form: (2x/x+2)=(3/x-2)-(12/x^2-4)

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Question 551700: Algebraically determine the EXACT roots in simplest form:
(2x/x+2)=(3/x-2)-(12/x^2-4)

Answer by KMST(5328) About Me  (Show Source):
You can put this solution on YOUR website!
I think you meant
2x%2F%28x%2B2%29 = 3%2F%28x-2%29 - 12%2F%28x%5E2-4%29.
I would start by multiplying both sides by a common denominator type of expression to eliminate denominators. (It's sort of the same as going to a common denominator and then working only with the numerators. However, you have to be aware that you may be introducing extraneous solutions that are solutions of the new equation, but make some of the original denominators zero.
Multiplying both sides by %28x%2B2%29%28x-2%29=x%5E2-4 we get

And then we re-arrange and simplify


Performing the indicated operations we go from
2x%28x-2%29=3%28x%2B2%29-12 to 2x%5E2-4x=3x%2B6-12 and to 2x%5E2-4x=3x-6
Then we add to both sides 6-3x
to get the quadratic equation
2x%5E2-7x%2B6=0 which we can solve by factoring
%282x-3%29%28x-2%29=0 --> x=2 or x=3%2F2
Or we could apply the quadratic formula to find the same solutions to the final equation.
However, x=2 is an extraneous solution. It's not a solution of the original equation, because it would make the denominators x-2 and x%5E2-4 zero.
THE SOLUTION
The only solution is x=3%2F2, which we verify:
For x=3%2F2, 2x%2F%28x%2B2%29 = 2%2A%283%2F2%29%2F%28%283%2F2%29%2B2%29 = 3%2F%287%2F2%29= 3%2A%282%2F7%29=6%2F7
and 3%2F%28x-2%29 - 12%2F%28x%5E2-4%29 = 3%2F%28%283%2F2%29-2%29 - 12%2F%28%283%2F2%29%5E2-4%29 = 3%2F%28-1%2F2%29 - 12%2F%28%289%2F4%29%5E-4%29 = 3%2A%28-2%2F1%29 - 12%2F%28-7%2F4%29 =-6-12%2A%28-4%2F7%29=-42%2F7%2B48%2F7=6%2F7
NOTES:
Parentheses are tricky.
(2x/x+2)=2x/x+2=2x%2Fx%2B2=2%2B2=4, but I think you meant 2x/(x+2)=2x%2F%28x%2B2%29
(3/x-2)-(12/x^2-4)=3/x-2-(12/x^2-4)=3%2Fx -2 - %2812%2Fx%5E2-4%29 = 3%2Fx -2 - 12%2Fx%5E2 +4 =3%2Fx - 12%2Fx%5E2 + 2,
but I think you meant 3%2F%28x-2%29 - 12%2F%28x%5E2-4%29.
The horizontal lines include invisible parentheses enclosing the expressions above and below them.
%281%2B2%2B3%2B4%29%2F%285%2B6%2B7%2B8%29=(1+2+3+4)/(5+6+7+8)
If you can only draw the slanted lines, you have to include the parentheses.