\(The\ formula\ of\ midpoint\ between\ (x_1;\ y_1)\ and\ (x_2;\ y_2)\\\\\left(\frac{x_1+x_2}{2};\ \frac{y_1+y_2}{2}\right)\\\\===================================\\(8;-9);\ (8;\ 5)\\\\\left(\frac{8+8}{2};\ \frac{-9+5}{2}\right)\to\left(\frac{16}{2};\ \frac{-4}{2}\right)\to\fbox{(8;-2)}\)
