Question

responda as questões a,b,c,d,e,f

Answer 1

(x-1).(x+5)=7
x²+5x-x-5=7
x²+4x-5-7=0
x²+4x-12=0

Δ=4²-4.1.-12
Δ=16+48
Δ=64

x=12+-√64/2
x=12+-8/2
x1=12+8/2
x1=20/2
x1=10
x2=12-8/2
x2=4/2
x2=2

LETRA B
(x-1)²=x+5
x²-2.x.1+1²=x+5
x²-2x+1-x-5=0
x²-3x-4=0

Δ=-3²-4.1.-4
Δ=9+16
Δ=25

x=-3+-√25/2
x=-3+-5/2
x1=-3-5/2
x1=-8/2
x1=-4
x2=-3+5/2
x2=2/2
x2=1

LETRA C
x+1.(x-2)=3
x²-2x+x-2=3
x²-x-2-3=0
x²-x-5=0

Δ=-1²-4.1.-5
Δ=1+20
Δ=21 nao tem raiz

LETRA D