Explicación paso a paso:
[tex] \frac{x}{2} + x = 13[/tex]
[tex] \frac{x + 2x}{2} = 13[/tex]
[tex] \frac{3x}{2} = 13 \\ 3x = 26 \\ x = \frac{26}{3} = [/tex]
x = 8,66
