Question

5-Resolva as equaçoes do 2° grau:
a)x² + 3x + 2 = 0

b)2x² + x - 1 = 0

c)4x² - 3x + 2 = 0

d)x² - 6x + 8 = 0

Answer 1

Resposta:

(A) x² + 3x + 2 = 0

3x = 0 - 2 - x²

3x = 0 + 3

3x = 3

x = 3/3

x = 1

(B) 2x² + x - 1 = 0

2x² = 0 - x + 1

2x² = 0 - 1x

4x = 1x

x = 4/1

x=4

(C) 4x² - 3x +2 = 0

4x² + 3x = 0 - 2

4x² - 3x = 0

16x + 3x = 0

19x = 0

x= 19

(D) x² - 6x + 8 = 0

6x = 0 + x² - 8

6x = 0 - 1 + 8

6x = 0 + 7

6x = 7

x = 7/6

x= 1