Respuesta :

Answer:

BE= 19

Step-by-step explanation:

   4x+3   = 12x-10

2(4x+3)   = 12x-10

  8x+6   = 12x-10

8x-8x+6 = 12x-8x-10

          6 = 4x-10

    10+6 = 4x-10+10

        16 = 4x

     16/4 = 4x/4

         4  = x

BE 8(4)+6   = 38         38/2 = 19

AC 12(4)-10 = 38

The diagonals of a rectangle are equal.