Question

Exercícios:

a) (x+3).(x-1)=4
b) 3x^2-5x+8=0
c) (x+3).(x-3)=5x-9
d) x^2+x(1-x)+5=0
e) x^2-3x+2=0

URGENTE!
ME AJUDEM POR FAVOR!

Answer 1

a) (x+3).(x-1)=4

x^2 + 2x - 3 = 4

x^2 + 2x + 1 - 1 - 3 = 4

(x + 1)^2 = 8

x1 = 2√2, x2 = -2√2

b) 3x^2-5x+8=0

delta d = 25 - 96 nao tem raiz real

c) (x+3).(x-3)=5x-9

x^2 - 9 = 5x - 9

x^2 - 5x = 0

x*(x - 5) = 0

x1 = 0, x2 = 5

d) x^2+x(1-x)+5=0

x^2 + x - x^2 + 5 = 0

x = -5

e) x^2-3x+2=0

delta

d = 9 - 8 = 1

x1 = (3 + 1)/2 = 2

x2 = (3 - 1)/2 = 1