3(a-2b)/4(a+2b)+(4a+8b)/(a-2b)
=3(a-2b)/4(a+2b)+4(a+2b)/(a-2b)
=(3/4)*(a-2b)/(a+2b)+4/[(a-2b)/(a+2b)]
=(3/4)*4+4/4
=3+1=4