Răspuns :
fie M mijlocul segmentului AB
xM=(xA+xB)/2, yM=(yA+yB)/2
XM=(1+5)/2=6/2=3
yM=(3-7)/2=-2
xM=(xA+xB)/2, yM=(yA+yB)/2
XM=(1+5)/2=6/2=3
yM=(3-7)/2=-2
[tex] x_{M}= \frac{ x_{A} + x_{B} }{2}= \frac{1-5}{2}=-2[/tex],si [tex] y_{M}= \frac{ y_{A} + y_{B} }{2}= \frac{3+7}{2}= \frac{10}{2}=5
[/tex], deci M(-2;5).