Similarity and Parallel

• 2

• 1/2

• 2/3

• 3/2

Tell whether the two figures are similar. Explain your reasoning. (Hint: are they proportional?)

• Yes, similar because they are the same shape and side lengths are proportional.

• No, not similar because they are the same shape, but side lengths are not proportional.

• Yes, same shape

• No, different sizes

If ΔABC, ΔZXY, ΔJLK, and ΔFGH are all similar, which statement is true?

• 
• 
• 
• 

What is the scale factor from ΔABC to ΔHGF?

• 1/9=.111

• 1/6=.167

• 1/4=.25

• 6

The triangles are similar, solve for the question mark.

• 8

• 12.5

• 18

• 24

Are the triangles similar?

• Yes

• No

What is the similarity statement for the triangle pair?

• ΔXYZ~ΔNEW

• ΔXZY~ΔNWE

• ΔZYX~ΔENW

• ΔYZX~ΔNWE

• 3 ∠ABF ≅ ∠DCF

  4 SAS Similarity

• 3 ∠A ≅ ∠D

  4 AA Similarity

• 3 ∠AFB ≅ ∠DFC

  4 AA Similarity

• 3 ∠ABF ≅ ∠DCF

  4 SAS SImilarity

• 2 ∠ACB ≅ ∠DCG Vertical angles are congruent

  3 ∠B ≅ ∠DCG Alternate exterior angles of parallel lines are congruent

• 2 ∠A ≅ ∠DCG Alternate interior angles of parallel lines are congruent

  3 m∠G + m∠ACB = 180 Same side interior angles of parallel lines are supplementary

• 2 ∠B ≅ ∠DCG Alternate interior angles of parallel lines are congruent

  3 ∠G ≅ ∠ACB Corresponding angles of parallel lines are congruent

• 2 ∠A ≅ ∠DCG Corresponding angles of parallel lines are congruent

  3 ∠G ≅ ∠ACB Corresponding angles of parallel lines are congruent

• 1 Given

  2 Given

  3 All right ∠s are ≅

  4 AA Similarity

  5 The ratio of the corresponding sides of similar Δs are in proportion

• 1 Given

  2 Given

  3 Vertical ∠s are ≅

  4 AA Similarity

  5 The ratio of the corresponding sides of similar Δs are in proportion

• 1 Given

  2 Given

  3 All right ∠s are ≅

  4 SAS Similarity

  5 The ratio of the corresponding sides of similar Δs are in proportion

• 1 Given

  2 Given

  3 Vertical ∠s are ≅

  4 SAS Similarity

  5 The ratio of the corresponding sides of similar Δs are in proportion