Question

x 3x

x+ ----- + ----- =18
2 4

me ajudem

Answer 1

x + x/2 + 3x/4 = 18

4x + 2x + 3x  =   72
-----------------      -----
       4                   4

9x = 72
x = 72/9
x = 8

Answer 2

$x + \dfrac{x}{2} + \dfrac{3x}{4} = 18 \\ \\ \dfrac{4x+2x+3x}{4} = 18 \\ \\ 9x= 18*4 \\ \\ 9x= 72\quad \to x= \dfrac{72}{9}\quad \to \boxed{x=8}$