Question

hallar x
7(8)9
12(8)4
9(x)31

Answer 1

Respuesta:

 7 (8) 9 → $\frac{7+9}{8}$ $=\frac{16}{2}=8$

12 (8) 4 → $\frac{12+4}{2} = \frac{16}{2}=8$

9 (x) 31 → $\frac{31 + 9 }{2}=\frac{40}{2}=20$

x = 20