Similar shapes: matching sides and angles
Grade 7 Math Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.
Milo compares two similar sails. Triangle ABC is similar to triangle FDE. How many cm long is side FD?
Noah compares two similar tent flaps. Triangle ABC is similar to triangle EFD. How many cm long is side FD?
Two triangles (the picture is not printed to size): ABC with AB = 5 cm, BC = 7 cm, AC = 9 cm; EFD with DE = 22.5 cm. Two triangles (the picture is not printed to size): ABC with AB = 5 cm, BC = 7 cm, AC = 9 cm; EFD with DE = 22.5 cm. A B C 5 cm 7 cm 9 cm E F D 22.5 cm Not to scale Bo has similar roof triangles A and B. Every side of B is 2 times as long as A's. A has angles of 50° and 55°. How big is B's angle matching A's third angle?
Triangle A with two angles marked, 50° and 55°, and a third angle unmarked; triangle B with one angle marked ? (the picture is not printed to size). Triangle A with two angles marked, 50° and 55°, and a third angle unmarked; triangle B with one angle marked ? (the picture is not printed to size). Triangle A 50° 55° Not to scale. Triangle B ? Not to scale. Jun has similar tent flaps A and B. Every side of B is 1.5 times as long as A's. A has angles of 40° and 45°. How big is B's angle matching A's third angle?
Triangle A with two angles marked, 40° and 45°, and a third angle unmarked; triangle B with one angle marked ? (the picture is not printed to size). Triangle A with two angles marked, 40° and 45°, and a third angle unmarked; triangle B with one angle marked ? (the picture is not printed to size). A 40° 45° Not to scale. B ? Not to scale. Luz cuts a small sail (A) and a bigger, similar sail (B), shown here. How many cm of rope go all the way around B's edge?
Triangle A with its three sides marked 6 cm, 8 cm and 10 cm; similar triangle B with the side matching A's 6 cm side marked 9 cm (the picture is not printed to size). Triangle A with its three sides marked 6 cm, 8 cm and 10 cm; similar triangle B with the side matching A's 6 cm side marked 9 cm (the picture is not printed to size). 6 cm 8 cm 10 cm Triangle A 9 cm Triangle B Not to scale Ren compares two tabletops. Table A is 12 by 20 dm and table B is 15 by 25 dm. Are A and B similar?
Sketch, not to scale: rectangle A is 12 by 20; rectangle B is 15 by 25. Sketch, not to scale: rectangle A is 12 by 20; rectangle B is 15 by 25. A 12 20 Not to scale. B 15 25 Not to scale. - Yes: both pairs of sides are × 5/4
- Yes: both rectangles are longer than they are wide
- No: the two tabletops are different sizes
- No: the short sides differ by 3 dm but the long sides differ by 5 dm
Tala sews two quilts. Quilt A is 3 by 5 feet and quilt B is 6 by 8 feet. Are A and B similar?
Sketch, not to scale: rectangle A is 3 by 5; rectangle B is 6 by 8. Sketch, not to scale: rectangle A is 3 by 5; rectangle B is 6 by 8. A 5 3 Not to scale. B 8 6 Not to scale. - No: 6 ÷ 3 = 2, but 8 ÷ 5 is not 2
- Yes: both sides are 3 feet longer
- No: quilt B is bigger than quilt A
- Yes: the short side doubled, 3 feet to 6 feet
Zee labels two similar roofs. Triangle ABC is similar to triangle FDE. Angle A is 40°. Which corner of triangle FDE has a 40° angle?
Two triangles (the picture is not printed to size): one with corners A, B, C, one with corners F, D, E. Two triangles (the picture is not printed to size): one with corners A, B, C, one with corners F, D, E. A B C F D E Not to scale - corner D
- corner E
- corner F
Ari labels two similar tent flaps. Triangle ABC is similar to triangle EFD. Angle B is 65°. Which corner of triangle EFD has a 65° angle?
Two triangles (the picture is not printed to size): one with corners A, B, C, one with corners E, F, D. Two triangles (the picture is not printed to size): one with corners A, B, C, one with corners E, F, D. A B C E F D Not to scale - corner D
- corner F
- corner E
One row 10 | 20 for the matching sides, with a box for the multiplier from B to A. Tala compares a kite design (A) and a bigger kite (B), similar shapes. A's tail is 10 cm and B's tail is 20 cm. What is the scale factor from B to A?