Year 9 Area and Perimeter Worksheet — Level 3 — 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 3 — Practice Set 3 — Answers
Write the formula, substitute, then calculate. Include units.
1.A triangle has a base of 6 cm and a perpendicular height of 5 cm. Find its area.
Answer: 15 cm2
- A = ½ × base × height = ½ × 6 × 5
- = 15 cm2
2.An L-shape is made from a 18 cm by 14 cm rectangle joined to a 5 cm by 16 cm rectangle. Find the total area.
Answer: 332 cm2
- Rectangle 1: 18 × 14 = 252
- Rectangle 2: 5 × 16 = 80
- Total: 252 + 80 = 332 cm2
3.A triangle has a base of 16 mm and a perpendicular height of 12 mm. Find its area.
Answer: 96 mm2
- A = ½ × base × height = ½ × 16 × 12
- = 96 mm2
4.A rectangle is 27 mm long and 11 mm wide. Find its area.
Answer: 297 mm2
- A = length × width = 27 × 11
- = 297 mm2
5.A rectangle is 24 mm long and 12 mm wide. Find its area.
Answer: 288 mm2
- A = length × width = 24 × 12
- = 288 mm2
6.A triangle has a base of 12 m and a perpendicular height of 10 m. Find its area.
Answer: 60 m2
- A = ½ × base × height = ½ × 12 × 10
- = 60 m2
7.A triangle has a base of 14 cm and a perpendicular height of 10 cm. Find its area.
Answer: 70 cm2
- A = ½ × base × height = ½ × 14 × 10
- = 70 cm2
8.An L-shape is made from a 19 m by 12 m rectangle joined to a 11 m by 7 m rectangle. Find the total area.
Answer: 305 m2
- Rectangle 1: 19 × 12 = 228
- Rectangle 2: 11 × 7 = 77
- Total: 228 + 77 = 305 m2
9.An L-shape is made from a 22 m by 11 m rectangle joined to a 9 m by 10 m rectangle. Find the total area.
Answer: 332 m2
- Rectangle 1: 22 × 11 = 242
- Rectangle 2: 9 × 10 = 90
- Total: 242 + 90 = 332 m2
10.A triangle has a base of 9 mm and a perpendicular height of 5 mm. Find its area.
Answer: 22.5 mm2
- A = ½ × base × height = ½ × 9 × 5
- = 22.5 mm2
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