soal tentang fungsi please bantuin

[tex] \frac{1}{2} [/tex] x + n = [tex] \frac{1}{2} [/tex] x +n
 [tex] \frac{1}{2} [/tex] (n + 1) + n = [tex] \frac{1}{2} [/tex] (2n -2) + n
[tex] \frac{1}{2} [/tex] n + [tex] \frac{1}{2} [/tex] + n = n -1 + n
[tex] \frac{3}{2} [/tex] n + [tex] \frac{1}{2} [/tex] = 2n - 1
[tex] \frac{3}{2} [/tex] n - 2n = -1 - [tex] \frac{1}{2} [/tex]
- [tex] \frac{1}{2} [/tex]  n = - [tex] \frac{3}{2} [/tex]
n = - [tex] \frac{3}{2} [/tex] x [tex] \frac{2}{-1} [/tex]
n = [tex] \frac{-6}{-2} [/tex]
n = 3