(4x+12)/(x^2+x-16)/(x-2)/(x+2)
=(4x+12)/(x^2+x-16)(x-2)(x+2)
=4(x+3)/(x^2+x-16)(x^2-4)
=4(-3(1/2)+3)/((-3(1/2))^2+(-3(1/2))-16)((-3(1/2))^2-4)
=4*(-1/2)/(49/4-7/2-16)(49/4-4)
=-2/(-29/4)(33/4)
=-2/(-957/16)
=32/957