Question

Resolva as equações incompletas

9$x^{2}$ - 4 = 0

-2$x^{2}$ + 8 = 0

$x^{2}$ - 49 = 0

Answer 1

9x² - 4 = 0

9x²= 0 + 4

9x² = 4

x²= √4/9

x= ± √4/9

x= ± 2/3

S= (2/3 , - 2/3)

- 2x² + 8 = 0

- 2x² = 0 - 8

- 2x² = - 8

x²= -8/-2

x²= 4

x= ± √4

x= ± 2

S= (2 , - 2)

x² - 49 = 0

x²= 0 + 49

x²= 49

x= ± √49

x= ± 7

S= ( 7 , - 7)