Relax

Respuesta :

I)

(2x -3)^2 - 2x(2x - 5)
= 4x^2 - 12x + 9 - 4x^2 + 10x
= -2x + 9 

II)
(2x+1)/3 = 1/2
2x + 1 = 3/2
2x = 1/2
  x = 1/4

III)
5 - (3x+4) >= 4
5 - 3x - 4 >= 4
-3x + 1 >= 4
-3x >= 3 
   x <= -1

iV)

2(x + x + 2) = 18
2(2x + 2) = 18
4x + 4 = 18
4x = 14
  x = 3.5 cm