1. Pair A shows two triangles:

△ABC: AB = 3 cm, BC = 4 cm, CA = 5 cm; angles are 40°, 60°, and 80°.

△DEF: DE = 6 cm, EF = 8 cm, FD = 10 cm; angles are 40°, 60°, and 80°; the second triangle is rotated.

Write the corresponding sides if A ↔ D, B ↔ E, and C ↔ F: AB ↔ ______, BC ↔ ______, CA ↔ ______.

2. Pair B shows enlarged rectangles:

▭ ABCD: 4 cm by 7 cm     ▭ EFGH: 8 cm by 14 cm

Are the rectangles similar? Circle one: Yes / No. State the scale factor from ABCD to EFGH.

3. Pair C shows two quadrilaterals:

◇ ABCD: sides 5 cm, 6 cm, 7 cm, 8 cm

◇ EFGH: corresponding sides 10 cm, 12 cm, 14 cm, 16 cm; the second shape is turned 90°.

Are the shapes similar? Circle one: Similar / Non-similar. Find the scale factor.

4. Pair D shows two triangles:

△JKL: sides 4 cm, 6 cm, 9 cm

△MNP: corresponding sides 8 cm, 12 cm, 15 cm

Are the shapes similar? Circle one: Similar / Non-similar. Identify the side ratios that support your answer.

5. Pair E shows two pentagons:

⬠ ABCDE has angles 100°, 110°, 90°, 120°, and 120°.

⬠ FGHIJ has corresponding angles 100°, 110°, 90°, 120°, and 120°; each side is 3 times the matching side of ABCDE.

Are the pentagons similar? Explain using one angle fact and one side-ratio fact.

6. Pair F shows two parallelograms:

▱ ABCD: adjacent sides 6 cm and 10 cm; angle A = 65°.

▱ EFGH: adjacent sides 9 cm and 15 cm; angle E = 65°.

Are the parallelograms similar? Circle one: Similar / Non-similar. Justify your decision.

7. Challenge: Two similar triangles have corresponding sides of 7 cm and 21 cm. A third corresponding side on the smaller triangle is 5 cm. Find the matching side on the larger triangle. Show your calculation.

8. In one or two sentences, explain how you can prove that two shapes are similar. Use the words corresponding, proportional, and scale factor.