Hi, can you help me please? :)
I'm going to assume that A is the center of the circle.
AC = AB since they're both the radius.
AD + EC = AB
Can you figure it out from here?
AB = AC = AD all radii.
I assume AE=7.5cm
radius = 7.5+5=12.5cm
Use pythagoras's theorum to find ED
then area of a triangle formula