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x^{2}  x  12 = (x + 3)(x  4) and hence two fractions in final equation in the line above can be written with a common denominator by multiplying the numerator and denominator of the left side by (x  4). Since the denominators are equal the numerators must be equal and hence
and thus
Substitute x = 32 into the other two equations. If the equations are all satisfied then x = 32 is the only solution. If one of the equations is not satisfied by x = 32 then there is no solution. Penny We received a reply
So the equation is My approach is to look for a common denominator. Since x^{2}  x  12 = (x + 3)(x  4) the common denominator I would use is (x + 3)(x  4)(x + 4). Writing each fraction with this denominator and simplifying leads to
I didn't see any obvious solution so I asked Wolfram Alpha to solve this equation. I don't think this was the problem you were intended to solve. My guess is that the denominator of the first fraction should be x  4 rather than x + 4. Penny  


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