Question

1) Resolva as seguintes equações do 2° grau, identifique os coeficientes e determine as raízes se existir.


d) x²-5x+8=0

e)2x²-8x+8=0

f)x²-4x-5=0

g)-x²+x+12=0

h)-x²+6x-5=0

i)6x²+x-1=0

j)3x²-7x+2=0

k)2x²-7x=15

l)4x²+9=12x

m)x²=x+12

n)2x²=-12x-8

o)x²+9=4x

p)25x²=20x-4

q)2x=15-x²

r)x²+3x-6=-8

s)x²+x-7=5

t)4x²-x+1=x+3x²

Answer 1

d)

a= 1, b = - 5, c = 8

Sem raízes

e)

a = 2, b = - 8, c = 8

x' = 0,8, x" = 4,8

f)

a = 1, b = - 4, c = - 5

x' = - 4, x" = 0

g)

a = - 1, b = 1, c = 12

x' = 4, x" = - 3

h)

a = - 1, b = 6, c = - 5

x' = 5, x" = 1

i)

a = 6, b = 1, c = - 1

x' = - 0,5 , x" = 0,333...

j)

a = 3, b = - 7, c = 2

x' = 0,333... , x" = 2

k)

a = 2, b = - 7, c = - 15

x' = - 1,5 , x" = 5

L)

a = 4, b = - 12, c = 9

x' e x" = - 1,1

m)

a = 1, b = - 1, c = - 12

x' = - 3, x" = 4

n)

a = 2, b = - 12, c = 8

x' = 0,765 , x" = 5,235

o)

a = 1, b = - 5, c = 8

Sem raízes

p)

a = 25, b = - 20, c = 4

x' e x" = 0,4

q)

a = 1, b = 2, c = - 15

x' = - 5, x" = 3

r)

a = 1, b = 3, c = 2

x' = - 2, x" = - 1

s)

a = 1, b = 1, c = - 12

x' = - 4, x" = 3

t)

a = 1, b = - 2, c = 1

x' e x" = 2