Question

resolva:

a)(2x+6).(5-x)›0
​

Answer 1

Explicação passo-a-passo:

Aplique a distributiva:

(2x+6).(5-x)›0

10x-2x²+30-6x>0

-2x²+4x+30>0

a)-2

b)4

c)30

∆= 4²-4.(-2).30

∆= 16 + 240

∆= 256

x= -4 +-√256

___________

2.(-2)

x1= -4-16/-4

x1= -20/-4

x1= 5

x2= -4+16/-4

x2= 12/-4

x2= -3

Answer 2

10x - 2 x² + 30 - 6x = 0
10x - 6x - 2 x² = -30
4x - 2 x² = 30