A triangle ABC is drawn to circumscribe a circle. If $AB=13$ cm, BC = 14cm and $AE=7$ cm, then AC is equal to

$AB=$ 13cm

$BC=$ 14cm

$AE=AF=7$

$AB=13$

$AF+FB=13$

$AF=13-FB$

$=13-7$

$=6$

$BF=BD=6$

$BC=14$

$BD+DC=14$

$6+DC=14$

$DC=14-6$

$=8$

$DC=CE=8$

$AC=AE+EC$

$=7+8$

$=15$