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7.3. OBJ: Show that two triangles are similar using the AA Similarity Postulate EQ: How do you show 2 triangles are similar?. Angle-Angle (AA) Similarity Postulate. If two angles of one triangle are congruent to two angles of another triangle, then the two triangles are similar.
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7.3 OBJ: Show that two triangles are similar using the AA Similarity Postulate EQ: How do you show 2 triangles are similar?
Angle-Angle (AA) Similarity Postulate • If two angles of one triangle are congruent to two angles of another triangle, then the two triangles are similar.
Determine whether the triangles are similar. If they are similar, write a similarity statement. Explain your reasoning. SOLUTION If two pairs of angles are congruent, then the triangles are similar. G Lbecause they are both marked as right angles. 1. Example 1 Use the AA Similarity Postulate
mF + 90°+ 61°= 180° Triangle Sum Theorem mF + 151° = 180° Add. Subtract 151° from each side. mF = 29° By the AA Similarity Postulate,FGH~ JLK ANSWER Find mFto determine whether Fis congruent to J. 2. Example 1 Use the AA Similarity Postulate Both Fand Jmeasure 29°, so F J.
Are you given enough information to show that RST is similar to RUV? Explain your reasoning. SOLUTION Redraw the diagram as two triangles: RUVand RST. Example 2 Use the AA Similarity Postulate RSTRUV. RRby the Reflexive Property of Congruence. Using AA Similarity Postulate, RST~RUV.
Checkpoint Determine whether the triangles are similar. If they are similar, write a similarity statement. 1. Use the AA Similarity Postulate
Checkpoint Determine whether the triangles are similar. If they are similar, write a similarity statement. 1. Use the AA Similarity Postulate
Checkpoint 2. yes; GLH~GKJ ANSWER Use the AA Similarity Postulate Determine whether the triangles are similar. If they are similar, write a similarity statement.
Checkpoint Write a similarity statement for the triangles. Then find the value of the variable. 3. Use Similar Triangles
Checkpoint Write a similarity statement for the triangles. Then find the value of the variable. 3. Use Similar Triangles 5 = 15 3 y 5y = 3(15) 5y = 45 Y = 9
Homework • Worksheet 7.3A • Quiz 7.1-7.3