Question

x(x-2)=2(x+6) por favor me ajudem!!

Answer 1

x (x - 2 ) = 2 ( x + 6 )
x² - 2x = 2x + 12
x² - 2x - 2x - 12 = 0
x² - 4x - 12 = 0

a = 1
b = - 4
c = - 12

Δ = b² - 4.a.c
Δ = ( - 4)² - 4 . 1 . ( - 12)
Δ = 16 + 48
Δ = 64

x = - b + -√Δ/2a
x = - ( - 4) + - √64/2 . 1
x = + 4 + - 8/2

x' = + 4 + 8 / 2 ⇒ x' = 12/2 ⇒ x' = 6
x" = + 4 - 8/ 2 ⇒ x" = - 4/ 2 ⇒ x" - 2

S = { - 2 e 6 }