Which one is false ?

Given: △abc, ab=15, bd=9 ad ⊥ bc , m∠c=30°. find: the perimeter of the triangle.

Which two undefined geometric terms always describe figures with no beginning or end?

1. 2. ∠b and ∠y are right angles. 3.? 4.? which two statements are missing in steps 3 and 4? ∠x ≅ ∠c △abc ~ △zyx by the sas similarity theorem. ∠b ≅ ∠y △abc ~ △zyx by the sas similarity theorem. = 2 △abc ~ △zyx by the sss similarity theorem. = 2 △abc ~ △zyx by the sss similarity theorem.