Question

Can someone explain this to me ​

Answer 1

Angle ADB is a right angle --- Given

Angle ADB is 90 degrees --- Definition of a Right Angle

Angle CDB is 90 degrees --- Definition of Supplementary Angles

Angle ADB = Angle CDB --- Definition of Congruent Angles

Proofs can be tricky! What helps me is thinking through them step by step and how I would prove I did something. While I'm not entirely sure what options you have for this proof, I've given my best guess.

Hope this helps!! :)