9th Grade Area and Perimeter Worksheet — Level 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 — Answers
Write the formula, substitute, then calculate. Include units.
1.A triangle has a base of 18 cm and a height of 11 cm. Find its area.
Answer: 99 cm2
- A = ½ × base × height = ½ × 18 × 11
- = 99 cm2
2.A rectangle is 20 m long and 8 m wide. Find its area.
Answer: 160 m2
- A = length × width = 20 × 8
- = 160 m2
3.An L-shape is made from a 14 m by 2 m rectangle joined to a 8 m by 6 m rectangle. Find the total area.
Answer: 76 m2
- Rectangle 1: 14 × 2 = 28
- Rectangle 2: 8 × 6 = 48
- Total: 28 + 48 = 76 m2
4.A triangle has a base of 20 mm and a height of 14 mm. Find its area.
Answer: 140 mm2
- A = ½ × base × height = ½ × 20 × 14
- = 140 mm2
5.A rectangle is 18 cm long and 13 cm wide. Find its area.
Answer: 234 cm2
- A = length × width = 18 × 13
- = 234 cm2
6.An L-shape is made from a 3 cm by 5 cm rectangle joined to a 2 cm by 6 cm rectangle. Find the total area.
Answer: 27 cm2
- Rectangle 1: 3 × 5 = 15
- Rectangle 2: 2 × 6 = 12
- Total: 15 + 12 = 27 cm2
7.A rectangle is 16 cm long and 9 cm wide. Find its area.
Answer: 144 cm2
- A = length × width = 16 × 9
- = 144 cm2
8.A triangle has a base of 8 m and a height of 3 m. Find its area.
Answer: 12 m2
- A = ½ × base × height = ½ × 8 × 3
- = 12 m2
9.A rectangle is 9 m long and 5 m wide. Find its area.
Answer: 45 m2
- A = length × width = 9 × 5
- = 45 m2
10.A rectangle is 9 cm long and 8 cm wide. Find its area.
Answer: 72 cm2
- A = length × width = 9 × 8
- = 72 cm2
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