Verified Answer :

x2+2x-8 =0
x2 + 4x - 2x - 8 = 0
x(x+4) - 2(x+4) = 0
(x-2)(x+4) = 0
let x- 2 = 0
x = 2
let x+4 = 0
x= -4

Ryan2

\(x^{2} +2x=8 \ add \ 1 \ to \ both \ sides\\ \\ x^{2} +x+8+1 \ in \ the \ left \ side \ you \ find \ a perfect \ square \ trinomial\\ \\ (x+1)^2=9\\ \\ So:\\ \\ x+1=\pm \sqrt{9}\\ \\ x+1=\pm 3\\ \\ x+1=3 \rightarrow x=2\\ \\ x+1=-3 \rightarrow \x=-4\)

Related Questions