Question

Alguém me ensina a resolver,plmds tenho prova às 08:00.

Answer 1

(X-2).(x+2)-(x-1)^2=x^2-8
x^2+2x-2x-4-x^2+2.x.(-1)+1^2=x^2-8
x^2-x^2-2x+2x-4-2x-1=x^2-8
-x^2-2x+8-4-1=0
-x^2-2x+3=0

Delta=b^2-4AC
Delta=4-4.(-1).3
delta=4+12
delta=16

X=1+4/2=5/2
x2=1-4/2=3/2