[tex]Zadanie\\\\Wspolrzedne\ srodka\ odcinka\ BC\\\\B=(0,-1),\ C=(6,5)\\\\S=(\frac{x_B+x_C}{2}\ ;\ \frac{y_B+y_C}{2})\\\\S=(\frac{0+6}{2}\ ;\ \frac{-1+5}{2})= (3,2)\\\\\\Dlugosc\ odcinka\ AS\\\\A=(-1,5),\ S=(3,2)\\\\\mid AS\mid=\sqrt{(x_S-x_A)^{2}+(y_S-y_A)^{2}}\\\\\mid AS\mid=\sqrt{[3-(-1)]^{2}+(2-5)^{2}}= \sqrt{4^2+(-3)^2}=\sqrt{16+9}=\sqrt{25}=5[/tex]
