Question

DOU 20 PONTOS
Resolva a equação do 2° grau: (2x-1).(x+2)=3x-7x².

Answer 1

(2x-1).(x+2)=3x-7x²

2x²+4x-x-2=3x-7x²

2x²+7x²+4x-3x-x-2=0

9x²-2=0

9x²=2

x²=2/9

x=+-√(2/9)

x=+-√2/3

S={-√2/3 , √2/3}