Question

Ajudem aqui para dia ( 03/09/2019 )

E) x² = x + 12

F) 2x = 15 - x²

G) 4x² - x + 1 = x + 3x²

H) x² + 3x - 6 = -8​

Answer 1

Explicação passo-a-passo:

E) x² = x + 12

x² -x-12=0

a) 1

b) -1

c) -12

∆= (-1)² -4.1.(-12)

∆= 1 + 48

∆= 49

x= -(-1) +- √49

____________

2.1

x1= 1+7 / 2

x1= 8/2

x1= 4

x2= 1-7/2

x2= -6/2

x2= -3

F) 2x = 15 - x²

x² + 2x - 15= 0

a) 1

b) 2

c) -15

∆= 2² -4.1.(-15)

∆= 4 + 60

∆= 64

x= -2 +- √64

_________

2.1

x1= -2 -8 / 2

x1= -10/2

x1= -5

x2= -2+8/2

x2= 6/2

x2= 3

G) 4x² - x + 1 = x + 3x²

4x² - 3x² -x -x +1= 0

x² -2x +1= 0

a) 1

b) -2

c) 1

∆= (-2)² -4.1.1

∆= 4-4

∆=0

x= -(-2) +-√0

__________

2.1

x1 e x2= 2/2

x1 e x2= 1

H) x² + 3x - 6 = -8

x² + 3x -6 +8= 0

x² +3x +2=0

a) 1

b) 3

c) 2

∆= 3² -4.1.2

∆= 9-8

∆=1

x= -3 +-√1

________

2.1

x1= -3-1/2

x1= -4/2

x1= -2

x2= -3+1/2

x2= -2/2

x2= -1

Espero ter ajudado :)