Question

Alguém pode me ajudar??

Answer 1

X considerado numero 1.

a) 4x²-x+1=x+3x²

   4x²-3x²-x-x=-1

   x²-2x=-1

   x²-2x+1=0

Formula:

D=1-4.4.1

D=1-16

D=-15(não tem raiz)

x1=-1+raiz de -15/2

x2=-1-raiz de -15/2

b)3x²+5x=-x-9+2x²

  3x²-2x²+5x+x=-9

  x²+6x=-9

  x²+6x+9=0

Formula:

D=36-4.1.9

D=36-36

D=0

x1=-6+0/2=-6/2=-3

x2=-6-0/2=-6/2=-3

c)4+x(x-4)=x

  4+x²-4x=x

  x²-4x-x=-4

  x²-5x+4=0

Formula:

D=25-4.1.4

D=25-16

D=9

D=3(raiz de 9)

x1=5-3/2=2/2=1

x2:5+3/2=8/2=4

d)x(x+3)-40=0

  x²+3x-40=0

  Formula:

   D=B²-4.a.c

   D=9-4.1.-40

   D=9+160

   D=169

   D=13(raiz de 169)

    x1=-3+raiz de 169/2=-3+13/2=10/2=5

    x2=-3-13/2=-16/2=-8