15−2x(x+4)(x−3)\frac{15 - 2x}{(x+4)(x-3)}(x+4)(x−3)15−2x = Rx+4\frac{R}{x+4}x+4R + 97(x−3)\frac{9}{7(x-3)}7(x−3)9
15-2x = R(x - 3) +9(x +4)/7
Put x =-4, we have 15 -2(-4) = -7R
23 -7R;
R = 23/7