Determinam coordonatele mijlocului segmentului AB:
[tex]M( \frac{x_A+x_B}{2} , \frac{x_A+x_B}{2})=M(0,1)\\
m_{AB}= \frac{y_B-y_A}{x_B-x_A} = \frac{-1-3}{1+1} =-2\\
m_{AB}\cdot m_{med} =-1\\
m_{med}= \frac{1}{2} \\
ec.med:y-y_M=m_{med}(x-x_{M})\\
ec.med:y-1= \frac{1}{2} x[/tex]