Question

Came up with a Geometry + Trig (multi-part) question. If any one wants to try it...

Answer 1

You have Quadrilateral ABCD with sides 12, 16, 20. & 24

AB=16, BC=12, CD=20, DA=24
m<B= 90

Part 1. (Geometry) Prove ABCD is a Trapezoid

Answer 2

Part 2. (Geometry) point O on Segment AB. AO=7.\[\text{Prove }m \angle DOB = 2 \cdot m \angle COB.\]

Answer 3

Part A :
1) Join C and the "midpoint" of AD