M______C______A___________N
Означаваме МN с y.Следователно МА=АN=1/2y
MC=X
CN=X+6
2X+6=y
2X=y-6
X=1/2y-3
=>CN=X+6=1/2y-3+6=1/2y+3
AN=1/2MN=1/2y
AC=CN-AN
AC=1/2y+3-1/2y
AC=3sm