Question

(5x+2). (2-x). (4x+3)> : 0

Answer 1

(5x+2).(2-x).(4x+3)>0
10x-5x²+20x²+15x+4-2x+8x+6>0
20x²-5x²+15x+10x-2x+8x+6+4>0
15x²+35x+10>0

15x²+35x+10=0
multiplicando o (a) pelo (c)
x²+35x+150=0
s=35 / p=150
x'=5 x"=30

S={5,30}

*espero ter ajudado :)