Question

Resolva agora você:

a) 9x? + 6x - 48 = 0
b) x² + 8x + 15 = 0
c) 5x? - 4x + 2 = 0
d) x (x - 1) = 11x - 36

Answer 1

a) 9x + 6x - 48 = 0 =

15x – 48 = 0 =

15x = 48 =

x = 16/5

b) x² + 8x + 15 = 0 =

x² + 5x + 3x + 15 = 0 =

x . ( x + 5 ) + 3x + 15 = 0 =

x . ( x + 5 ) + 3 ( x + 5 ) = 0 =

( x + 5 ) . ( x + 3 ) = 0 =

x + 5 = 0 =

x + 3 = 0 =

x = –5 =

x = –3 =

x¹ = –5, x² = –3

c) 5x ‐ 4x + 2 = 0 =

9x + 2 = 0 =

9x = –2 =

x = – 2/9

d) x (x - 1) = 11x - 36 =

x² – x = 11x – 36 =

x² – x – 11x + 36 = 0 =

x² – 12x + 36 = 0 =

( x – 6)² = 0 =

x – 6 = 0 =

x = 6

ASS: Blues | 20/08/21 às 11:02