Question

d) ( x + 5 )² = ( 2x - 3 )²​

Answer 1

Resposta:

- 8 ; 2/-3

Explicação passo-a-passo:

(x + 5)² = (2x - 3)²

(x + 5) • (x + 5) = ( 2x - 3) • (2x - 3)

x² + 5x + 5x + 25 = 4x² - 6x - 6x + 9

x² + 10x + 25 = 4x² - 12x + 9

x² - 4x² + 10x + 12x + 25 - 9 = 0

- 3x² + 22x + 16 = 0

A= - 3

B= 22

C= 16

∆= b² - 4ac

∆= 22² - 4 • ( - 3) • 16

∆= 484 + 192

∆= 676

x= - b ± √∆/2a

x= - 22 ± √676/2 • ( - 3)

x= - 22 + 26/ - 6 = 4/-6 = 2/-3

x''= - 22 - 26/-6 = 48/-6 = - 8

S= ( - 8 ; 2/-3)

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