Question

2 x² -16x=0 e 5 x² -20x=0 e 8 x²+8x=0

Answer 1

2 x² - 16 =0
x(2 x - 16 )=0
x´= 0
2 x - 16 = 0
2 x = 16
x = 16/2
x" = 8

5 x² - 20 x = 0
x(5 x - 20 ) = 0
x´=0
5 x - 20 = 0
5 x = 20
 x = 20/5
x" = 4

8 x² + 8 x = 0
x(8 x + 8 ) = 0
x´= 0
8 x + 8 = 0
8 x = - 8
x = -8/8
x" =  -1