Year 9 Area and Perimeter Worksheet — Level 2 — Practice Set 4 — 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 4 — Answers
Write the formula, substitute, then calculate. Include units.
1.A triangle has a base of 9 m and a perpendicular height of 8 m. Find its area.
Answer: 36 m2
- A = ½ × base × height = ½ × 9 × 8
- = 36 m2
2.A triangle has a base of 4 cm and a perpendicular height of 13 cm. Find its area.
Answer: 26 cm2
- A = ½ × base × height = ½ × 4 × 13
- = 26 cm2
3.A triangle has a base of 12 cm and a perpendicular height of 12 cm. Find its area.
Answer: 72 cm2
- A = ½ × base × height = ½ × 12 × 12
- = 72 cm2
4.A rectangle is 29 m long and 13 m wide. Find its area.
Answer: 377 m2
- A = length × width = 29 × 13
- = 377 m2
5.A triangle has a base of 9 mm and a perpendicular height of 15 mm. Find its area.
Answer: 67.5 mm2
- A = ½ × base × height = ½ × 9 × 15
- = 67.5 mm2
6.A rectangle is 30 mm long and 3 mm wide. Find its perimeter.
Answer: 66 mm
- P = 2 × (30 + 3)
- = 2 × 33 = 66 mm
7.A rectangle is 12 m long and 12 m wide. Find its perimeter.
Answer: 48 m
- P = 2 × (12 + 12)
- = 2 × 24 = 48 m
8.A rectangle is 8 mm long and 18 mm wide. Find its area.
Answer: 144 mm2
- A = length × width = 8 × 18
- = 144 mm2
9.A triangle has a base of 8 cm and a perpendicular height of 8 cm. Find its area.
Answer: 32 cm2
- A = ½ × base × height = ½ × 8 × 8
- = 32 cm2
10.A rectangle is 20 cm long and 13 cm wide. Find its area.
Answer: 260 cm2
- A = length × width = 20 × 13
- = 260 cm2
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