Question

Resolver correctamente las ecuaciones a. 10x + 2 + 5x = 7x - x + 20 b. 28 – 11x + 3 – 9x = 7 – 15x + 16 c. 6x – ( 3x + 2 ) = 9 – ( 4x – 10) d. 3x + [-5x – ( x + 3 )] = 8x – ( 5x - 9) e. 5x + 2( x - 3 ) = 7 – 4( 2x + 1) f. 3( x – 5 ) +2( 5 + 4x ) = 2(4x +1 ) + 5( 2x – 1) g) (2x + 5).(x – 4) = x(x +1) + x( x – 2

Answer 1

Respuesta:

Explicación:

a. 10x + 2 + 5x = 7x - x + 20

   15x +2 = 6x + 20

    15x - 6x = 20 - 2

    9x = 18

    x= 18/9

    x= 2

b. 28 – 11x + 3 – 9x = 7 – 15x + 16

   28 + 3 - 20x = +23 - 15x

   31 - 20x = 23 -15x

    31 -23  = -15x +20x

     8 = 5x

     8/5 = x

c. 6x – ( 3x + 2 ) = 9 – ( 4x – 10)

    6x -3x -2 = 9 -4x +10

    3x -2 = 19 -4x

    3x + 4x = 19 + 2

    7x = 21

     x= 21/7

     x= 3

d. 3x + [-5x – ( x + 3 )] = 8x – ( 5x - 9)

    3x + [-5x –  x - 3 )] = 8x -5x +9

    3x + [ -6x -3 ] = 3x + 9

    3x - 6x - 3 = 3x + 9

    -3x + 3x = 9 + 3

                   = 12

 e. 5x + 2( x - 3 ) = 7 – 4( 2x + 1)

     5x +2x - 6 = 7 - 8x - 4

      7x - 6 = 3 - 8x

     -6 -3 = -8x -7x

       -9 = -15x

        x= 9/15

f. 3( x – 5 ) +2( 5 + 4x ) = 2(4x +1 ) + 5( 2x – 1)

  3x - 15 + 10 + 8x = 8x + 2 + 10x - 5

  11x -5 = 18x -3

   -5 +3 = 18x -11x

    -2 = 7x

     x= 2/7

g) (2x + 5).(x – 4) = x(x +1) + x( x – 2)

    2x-8x+5x-20 = x + 1 + x - 2x

     -6x + 5x -20 = 1

     -x -20 = 1

     -x= 1 + 20

     -x= 21

      21= x