Question

4+x(x-4)=x me ajudem

Answer 1

4 + x.(x - 4) = x

4 + x.x - 4.x = x

4 + x² - 4x = x

x² - 4x - x + 4 = 0

x² - 5x + 4 = 0

Δ = b² - 4.a.c

Δ = -5² - 4 . 1 . 4

Δ = 25 - 4. 1 . 4

Δ = 9

Há 2 raízes reais.

x = (-b +- √Δ)/2a

x' = (--5 + √9)/2.1

x'' = (--5 - √9)/2.1

x' = 8 / 2

x'' = 2 / 2

x' = 4

x'' = 1