Transcript 7-3 Proving Triangles Similar

7-3 Proving Triangles Similar
Triangle Similarity
Angle-Angle Similarity Postulate: If two angles of
one triangle are congruent to two angles of
another triangle, then the triangles are similar.
Side-Angle-Side Similarity Theorem: If an angle of
one triangle is congruent to an angle of a second
triangle, and the sides that include the two angles
are proportional, then the triangles are similar.
Side-Side-Side Similarity Theorem: If the
corresponding sides of two triangles are
proportional, then the triangles are similar.
Using the AA Similarity Postulate
• Are the two triangles similar?
 Are the two triangles similar?
Verifying Triangle Similarity
• Are the triangles similar? Explain. If so, write
a similarity statement.
 Are the triangles similar? Explain.
If so, write a similarity statement.
Finding Lengths in Similar Triangles
• You can use indirect measurement to find lengths that are
difficult to measure directly.
• You want to know the height of a cliff, so you place a mirror
on the ground and walk backwards until you can see the top
of the cliff in the mirror. What is the height of the cliff?