Question

Resolva as seguintes equações: a) (2x+1)² = (3x-1) (5x-1) b) (2x-3) (x+4) = (x+2) (5x-6)

Answer 1

a) ( 2x+1)²= (3x-1) (5x-1)

    (2x+1)(2x+1)= (3x-1)(5x-1)

  4x²+2x+2x+1= 15x²-2x-5x+1

4x²+4x+1=15x²-8x+1

4x²+4x+1-15x²+8x-1=0

-11x²=12x+1-1=0

-11x²+12x=0 (-1)

11x²-12x=0

 

x=-(-12) + ou - raiz quadrada de (-12)² -4.11.0

    -----------------------------------------------------------

                          2.11

 

x1=12+12     24:2

      ---------= ------=12/11

         22         22:2

x2=12-12/22=0