Question

resolva as equações de 2° grau
a) x²-5x+6=0
b) x²-8x+12=0
c) x²+2x-8=0

Answer 1

a) x²-5x+6=0
x=-b +ou- √b²-4ac/2a
x=5 +ou- √25-24/2
x=5 +ou- √1/2
x=5 +ou- 1/2
x'= 5+1/2= 3
x"= 5-1/2= 2

b) x²-8x+12=0
x=-b +ou- √b²-4ac/2a
x=8 +ou- √64-48/2
x= 8 +ou- √16/2
x= 8 +ou- 4/2
x'=  8 +4/2 = 6
x"= 8 - 4/2 = 2

c)b) x²+2x-8=0
x=-b +ou- √b²-4ac/2a
x=-2 +ou- √4+32/2
x= -2 +ou- √36/2
x= -2 +ou- 6/2
x'=  -2 +6/2 = 2
x"= -2 - 6/2 = -4