Year 9 Area and Perimeter Worksheet — Level 2 — Practice Set 3 — Answers
Answer sheet with worked solutions for the Year 9 area & perimeter worksheet.
Success TutoringWorksheetsAnswer sheetYear 9 · Mathematics · Area & PerimeterYear 9 Area and Perimeter Worksheet — Level 2 — Practice Set 3 — Answers
Write the formula, substitute, then calculate. Include units.
1.A triangle has a base of 19 m and a perpendicular height of 5 m. Find its area.
Answer: 47.5 m2
- A = ½ × base × height = ½ × 19 × 5
- = 47.5 m2
2.A rectangle is 19 m long and 11 m wide. Find its area.
Answer: 209 m2
- A = length × width = 19 × 11
- = 209 m2
3.A rectangle is 20 m long and 16 m wide. Find its perimeter.
Answer: 72 m
- P = 2 × (20 + 16)
- = 2 × 36 = 72 m
4.A rectangle is 21 cm long and 8 cm wide. Find its area.
Answer: 168 cm2
- A = length × width = 21 × 8
- = 168 cm2
5.A rectangle is 28 cm long and 13 cm wide. Find its area.
Answer: 364 cm2
- A = length × width = 28 × 13
- = 364 cm2
6.A triangle has a base of 11 cm and a perpendicular height of 3 cm. Find its area.
Answer: 16.5 cm2
- A = ½ × base × height = ½ × 11 × 3
- = 16.5 cm2
7.A rectangle is 20 m long and 12 m wide. Find its area.
Answer: 240 m2
- A = length × width = 20 × 12
- = 240 m2
8.A rectangle is 9 mm long and 8 mm wide. Find its perimeter.
Answer: 34 mm
- P = 2 × (9 + 8)
- = 2 × 17 = 34 mm
9.A rectangle is 8 mm long and 11 mm wide. Find its perimeter.
Answer: 38 mm
- P = 2 × (8 + 11)
- = 2 × 19 = 38 mm
10.A rectangle is 10 cm long and 17 cm wide. Find its perimeter.
Answer: 54 cm
- P = 2 × (10 + 17)
- = 2 × 27 = 54 cm
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