(8a/a^2-b^2 3/b-a - 4/a b ): 1/5a-5b

=(8a+3a+3b-4a+4b)/a^2-b^2 : 1/5a-5b= 7a+7b/(a+b)(a-b):1/5(a-b)=7(a+b)/(a+b)(a-b):1/5(a-b) = 7/(a-b):1/5(a-b)=7*5(a-b)/(a-b)=7*5/1=35