Question

Equação do 2 grau sendo u=r
A)X2-16=0
B)2x2-18=
C)x2-5x=0
D)3x2+2x=0
E)x2+3x+2x=0

Answer 1

a) x²-16=0
x²=16
x=±√16
x=±4

b)2x²-18=0
2x²=18
x²=18/2
x²=9
x=±√9
x=±3

c)x²-5x=0
x(x-5)=0
x1=0
x2= 5

d) 3x²+2x=0
∆=2²-4.3.0
∆= 4
x= -2±√4/2.3
x= -2±2/6
x1= -2+2/6= 0/6=0
x2= -2-2/6= -4/6= -2/3

e)x²+3x+2x=0
x²+5x=0
x(x+5)=0
x1=0
x2= -5