Question 875477
number 1 is the original problem as i see it.
number 2 is the result of multiplying the original problem by ab/ab.
this removes the denominators in each of the numerator and denominator of the original expression.
number 3 is the result of a^2 - b^2 = (a-b) * (a+b) and the result of ab + a^2 = a * (b + a) 
number 4 is the result of a * (b + a) being the same as a * (a + b)
number 5 cancels out (a + b) in the numerator and the (a + b) in the denominator to get the answer.
here's the written details of the solution to the problem.
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