Question

(×-5)2=2×.(×-5) Quanto e

Answer 1

2x - 10 = 2x . (x-5)

2x - 10 = 2x² - 10x

2x² - 12x + 10

Δ = 144 - 80

Δ = 64

x= -b +- √Δ / 2a

x1 = 12 + 8 / 4

x1 = 20/ 4

x1 = 5

x2 = 12 - 8 /4

x2 = 4/4

x2 = 1

S={5,1}