Question

Quanto e que vai dar essa conta de equação de 2 grau:

A) 9x2=5x

B) 5x2=-10x

Answer 1

A)
9x²=5x
9x²-5x=0
x(9x-5)=0

x'=0
x"= 9x-5=0
x"= x=5/9

S={0;5/9}

B)
5x²=-10x
5x²+10x=0
x(5x+10)=0
x'=0
x"= 5x+10=0
x"= 5x=-10
x"= -2

S={0;-2}

bons estudos

Answer 2

Olá,

a)

9x² = 5x
9x²-5x = 0
x·(9x-5) = 0

x = 0

ou 

9x-5 = 0
9x = 5
x = 5/9

Resposta: S = {0,5/9}

b)

5x² = -10x
5x²+10x = 0
5x·(x+2) = 0

5x = 0
x = 0/5
x = 0

ou 

x+2 = 0
x = -2

Resposta: S = {0,-2}