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Question

Simplify this expression


x ^2 - 64 / x + 8
_______ ______
x ^2 -25 / x - 5

Answer 1

Top line (Numerator) :-
N = (x - 8).(x + 8) / (x + 8)
N = (x - 8)

Bottom Line (Denominator):-
D = (x - 5).(x + 5) / (x - 5)
D = (x + 5)

N/D = (x - 8) / (x + 5)

Answer 2

Notice x^2-64 = (x+8)(x-8). So (x^2-64)/(x+8) = x-8. Similarly x^2-35 = (x-5)(x+5). So, (x^2-25)/(x-5)=x+5. So this reduces to x-8/x+5