Question

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

Answer 1

4 + x(x - 4) = x
4 + x² - 4x = x
x² - 4x - x + 4 = 0
x² - 5x + 4 = 0
Δ = (-5)² - 4(1)(4)
Δ = 25 - 16
Δ = 9
$x = \frac{5\pm3}{2} \\ \\ x' = 4 \\ x'' = 1$

Answer 2

Olá,

4 + x(x-4) = x
4 + x² - 4x = x
x² - 4x - x + 4 = 0
x² - 5x + 4 = 0
Δ = (-5)² - 4*1*4
Δ = 25 - 16
Δ = 9

x1 = [-(-5) + √9]/2*1
x1 = (5+3)/2
x1 = 8/2
x1 = 4

x2 = [-(-5) - √9]/2*1
x2 = (5-3)/2
x2 = 2/2
x2 = 1

S = {4,1}

Bons estudos ;)