Question

1) Resolva a equações do 2° grau:

a) 2x² + x – 3 = 0

b) X 2 – 5x + 6 = 0

c) X 2 = 25

d) X 2 + 5x = 0

Answer 1

Resposta: A) X'= 1 ; X"= -1,5

B) X'= 3 ; X"= 2

C) X'= 5 ; X"= -5

D) X'= 0 ; X"= -5

Explicação passo a passo:

A) 2X²+X-3= 0

Delta= 1²-4×2×-3

Delta= 25

X'= -1+5/4

X'= 1

X"= -1-5/4

X"= -6/4

X"= -1,5

B) X²-5x+6=0

Delta= -5²-4×1×6

Delta = 1

X'= -(-5)+1/2

X'= 6/2

X'= 3

X"= -(-5)-1/2

X"= 4/2

X"= 2

C) X²=25 (B= 0)

X'= Raiz quadrada de 25

X'= 5

X"= -(Raiz de 25)

X"= -5

D) X² + 5x = 0 (C=0)

Delta= 5²-4×1×0

Delta= 25

X'= -5+5/2

X'= 0

X"= -5-5/2

X"= -10/2

X"= -5