(5х-1)/( х+7)-(2х+2)/(х-3)+63/(х^2+4x-21)=0

Question

(5х-1)/( х+7)-(2х+2)/(х-3)+63/(х^2+4x-21)=0

Answer 1

X²+4x-21=0
x1+x2=-4 U x1*x2=-21⇒x1=-7 U x2=3
(5x-1)/(x+7)-(2x+2)/(x-3)=63/[9x+7)(x-3)]=0
x≠-7 x≠3
(5x-1)(x-3)-(2x+2)(x+7)-63=0
5x²-15x-x+3-2x²-14x-2x-14+63=0
3x²-32x+52=0
D=1024-624=400
x1=(32-20)/6=2
x2=(32+20)/6=26/3