Question

URGENTE
4 + x ( x - 4) = x ?????????

Answer 1

Explicação passo-a-passo:

4 + x ( x - 4) = x

4 + x² - 4x - x = 0

x² - 5x + 4 = 0

a= 1; b = -5; c = 4

D = -5² - 4 . 1 . 4

D = 25 - 16

D = 9

x' = (-(-5) + 3)/(2 . 1)

x' = (5 + 3)/(2)

x' = (8)/(2)

x' = 4

x" = (-(-5) - 3)/(2 . 1)

x" =( 5 - 3)/( 2)

x'' = (2)/( 2)

x'' = 1

S = {(1, 4)}