Similar shapes: matching sides and angles

Answer Key - Grade 7 Math Worksheet - Challenge Me

Circle the best answer, or write your answer on the line.

1. 1.

   One row 25 | 10 for the matching sides, with a box for the multiplier from A to B. Jun copies a big model door (A) into a small model (B), similar shapes. A is 25 cm tall and B is 10 cm tall. What is the scale factor from A to B?

   0.4
2. 2.

   One row 12 | 3 for the matching sides, with a box for the multiplier from A to B. Kira copies a kite design (A) onto a tiny sticker (B), similar shapes. A's tail is 12 cm and B's tail is 3 cm. What is the scale factor from A to B?

   0.25
3. 3.

   Noah compares two similar tent flaps. Triangle ABC is similar to triangle EFD. How many cm long is side FD?

   17.5
4. 4.

   Milo builds a small ramp (A) and a bigger, similar ramp (B), shown here. How many cm of tape go all the way around B's edge?

   47.5
5. 5.

   Ren compares two tabletops. Table A is 12 by 20 dm and table B is 15 by 25 dm. Are A and B similar?

   • No: the short sides differ by 3 dm but the long sides differ by 5 dm
   • Yes: both rectangles are longer than they are wide
   • No: the two tabletops are different sizes
   • Yes: both pairs of sides are × 5/4
6. 6.

   Tala sews two quilts. Quilt A is 3 by 5 feet and quilt B is 6 by 8 feet. Are A and B similar?

   • No: quilt B is bigger than quilt A
   • No: 6 ÷ 3 = 2, but 8 ÷ 5 is not 2
   • Yes: both sides are 3 feet longer
   • Yes: the short side doubled, 3 feet to 6 feet
7. 7.

   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?

   • corner F
   • corner E
   • corner D
8. 8.

   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?

   • corner F
   • corner E
   • corner D
9. 9.

   Bo labels two similar ramps. Triangle PQR is similar to triangle YZX. Angle Q is 25°. Which corner of triangle YZX has a 25° angle?

   • corner Y
   • corner X
   • corner Z
10. 10.

    Esme labels two similar roofs. Triangle LMN is similar to triangle STU. Angle M is 30°. Which corner of triangle STU has a 30° angle?

    • corner U
    • corner S
    • corner T