Question

Determine os valores reais de x que tornam a função positiva, negativa ou nula. a) y=2x-8 b) y=-2x-4

Answer 1

a)

2x-8= 0

2x = 8

x = 4

2x - 8 > 0

2x > 8

x > 4

2x - 8 < 0

2x < 8

x < 4

B)

-2x-4=0

-2x= 4

x = -2

-2x -4>0

-2x>4

x<-2

-2x-4<0

-2x<4

2x > -4

x > -2