Question

(5x-2)ao quadrado =64

Answer 1

(5x - 2)² - 64 = 0

25x² - 20x + 4 - 64 = 0

25x² - 20 x - 60 = 0 (simplificando tudo por 5)

5x² - 4x - 12 = 0

Δ = b² - 4 ac

Δ = 16 - 4 . (5) . (-12)

Δ = 16 + 240

Δ = 256

$x = \frac{- b +- \sqrt{D} }{2a}$

x = 4 + - 16 / 10

x' = 2

x" = -12/10 = - 6/5