9th Grade Area and Perimeter Worksheet — Level 3 — Practice Set 3 — Answers
Answer sheet with worked solutions for the 9th Grade area & perimeter worksheet.
Success TutoringWorksheetsAnswer sheet9th Grade · Mathematics · Area & Perimeter9th Grade 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 14 m and a height of 3 m. Find its area.
Answer: 21 m2
- A = ½ × base × height = ½ × 14 × 3
- = 21 m2
2.A rectangle is 4 m long and 7 m wide. Find its area.
Answer: 28 m2
- A = length × width = 4 × 7
- = 28 m2
3.An L-shape is made from a 23 m by 14 m rectangle joined to a 14 m by 12 m rectangle. Find the total area.
Answer: 490 m2
- Rectangle 1: 23 × 14 = 322
- Rectangle 2: 14 × 12 = 168
- Total: 322 + 168 = 490 m2
4.A rectangle is 9 cm long and 11 cm wide. Find its area.
Answer: 99 cm2
- A = length × width = 9 × 11
- = 99 cm2
5.An L-shape is made from a 12 cm by 12 cm rectangle joined to a 9 cm by 2 cm rectangle. Find the total area.
Answer: 162 cm2
- Rectangle 1: 12 × 12 = 144
- Rectangle 2: 9 × 2 = 18
- Total: 144 + 18 = 162 cm2
6.An L-shape is made from a 6 m by 6 m rectangle joined to a 4 m by 3 m rectangle. Find the total area.
Answer: 48 m2
- Rectangle 1: 6 × 6 = 36
- Rectangle 2: 4 × 3 = 12
- Total: 36 + 12 = 48 m2
7.A rectangle is 29 mm long and 12 mm wide. Find its area.
Answer: 348 mm2
- A = length × width = 29 × 12
- = 348 mm2
8.A triangle has a base of 5 mm and a height of 13 mm. Find its area.
Answer: 32.5 mm2
- A = ½ × base × height = ½ × 5 × 13
- = 32.5 mm2
9.A rectangle is 18 mm long and 16 mm wide. Find its area.
Answer: 288 mm2
- A = length × width = 18 × 16
- = 288 mm2
10.A triangle has a base of 5 cm and a height of 3 cm. Find its area.
Answer: 7.5 cm2
- A = ½ × base × height = ½ × 5 × 3
- = 7.5 cm2
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