Question 975747


{{{(x^12)^5*(x^-2)^9*_a_ =(x^40)^5}}}

{{{(x^60)*(1/x^2)^9*a =x^200}}}

{{{(x^60)*(1/x^18)*a=x^200}}}

{{{(x^60/x^18)*a =x^200}}}

{{{x^(60-18)*a =x^200}}}

{{{x^42*a =x^200}}}

{{{a =x^200/x^42}}}

{{{a =x^(200-42)}}}

{{{a =x^158}}}

or {{{a =(x^79)^2}}}