Question 623410
{{{(a-6)/(a+15) = (2a)/(2a+6)}}}


{{{(a-6)(2a+6) = 2a(a+15)}}}


{{{2a^2+6a-12a-36 = 2a(a+15)}}}


{{{2a^2+6a-12a-36 = 2a^2+30a}}}


{{{2a^2+6a-12a-36 - 2a^2-30a = 0}}}


{{{-36a-36 = 0}}}


{{{-36a = 36}}}


{{{a = 36/(-36)}}}


{{{a = -1}}}


So the solution is {{{a = -1}}}


Remember to check your answer. I'll let you do this.