Question

Atividades pontos ( 7,0 ) Por favor qualguem me ajuda.

1) Resolva as eq. 2 grau.

a) x+8x+12=0 b) x-4x-12=0

Answer 1

a)x²+8x+12=0
Δ=b²-4.a.c
Δ= 8²-4.1.12
Δ=64-48
Δ=16

x=$x=\frac{-b+/- \sqrt{Δ} }{2.a}$
x=$x= \frac{-8+ ou - \sqrt{16} }{2.1}$
$x' = \frac{-8+4}{2} = \frac{-4}{2} =-2$
$x''= \frac{-8-4}{2} = \frac{-12}{2}=-6$

b) x²-4x-12=0
Δ=b²-4.a.c
Δ=-4²-4.1.(-12)
Δ=16+48
Δ=64

x=$x=\frac{-b+/-sqrt{Δ} }{2.a}$
x=$x= \frac{-(-4)+ ou - \sqrt{64} }{2.1}$
$x' = \frac{4+8}{2} = \frac{12}{2} =6$
$x''= \frac{4-8}{2} = \frac{-4}{2}=-2$