Question

Quanto é:
(x-5)²=25-9x

Answer 1

Resposta:

(x - 5)² = 25 - 9x

(x - 5) (x - 5) = 25 - 9x

x² - 5x - 5x + 25 = 25 - 9x

x² - 10x + 25 = 25 - 9x

x² - 10x + 25 - 25 + 9x = 0

x² - 10x + 9x = 0

a = 1

b = -10

c = 9

Delta = b² - 4ac

Delta = (-10)² - 4(1)(9)

Delta = 100 - 36

Delta = 64

X = (-b +- raiz de 64) : 2a

X = (10 +- 8) : 2

x' = (10 + 8) : 2

x' = 18 : 2

x' = 9 ←←←←←←←

x" = (10 - 8) : 2

x" = 2 : 2

x" = 1 ←←←←←←←

Espero ter te ajudado!