Main content
Course: High school geometry?>?Unit 4
Lesson 6: Proving relationships using similarity- Pythagorean theorem proof using similarity
- Exploring medial triangles
- Proof: Parallel lines divide triangle sides proportionally
- Prove theorems using similarity
- Proving slope is constant using similarity
- Proof: parallel lines have the same slope
- Proof: perpendicular lines have opposite reciprocal slopes
? 2024 Khan AcademyTerms of usePrivacy PolicyCookie Notice
Prove theorems using similarity
Problem
In the following triangle, .
Below is the proof that . The proof is divided into two parts, where the title of each part indicates its main purpose.
Complete part B of the proof.
Part A: Prove
Part B: Prove
Statement | Reason | |
---|---|---|
8 | Reflexive property | |
9 | similarity (Part A, 8) | |
10 | Measures of corresponding angles of similar triangles are equal. (9) | |
11 | If a transversal crosses two lines and | angles are congruent, then the lines are parallel. (10)