The arc mCAD is 288.
Given: DAB and DCB are right angles; BDC = 54°
Required: arc mCAD
Solution:
(2 x 54°) + (2 x 54°) + (2 x 36°) = 288
Note: in getting 36°, deduct 54° and 90° (right angle) from 180° (which is the total degrees inside a triangle)
= 180° - 54° - 90°
= 36° - this is the angle CBD or angle ABD
