Let's solve each of the 2D shapes' areas step by step using the appropriate formulas.
---
1) Square
- Side = 9 cm
-
Area of a square = side × side
$$
\text{Area} = 9 \times 9 = 81\, \text{cm}^2
$$
✔ Answer: 81 cm²
---
2) Rectangle
- Length = 7 cm, Width = 2 cm
-
Area of a rectangle = length × width
$$
\text{Area} = 7 \times 2 = 14\, \text{cm}^2
$$
✔ Answer: 14 cm²
---
3) Right-Angled Triangle
- Base = 4 cm, Height = 8 cm
-
Area of a triangle = $\frac{1}{2} \times \text{base} \times \text{height}$
$$
\text{Area} = \frac{1}{2} \times 4 \times 8 = 16\, \text{cm}^2
$$
✔ Answer: 16 cm²
---
4) Triangle
- Base = 5 cm, Height = 12 cm
- Again, use: $\frac{1}{2} \times \text{base} \times \text{height}$
$$
\text{Area} = \frac{1}{2} \times 5 \times 12 = 30\, \text{cm}^2
$$
✔ Answer: 30 cm²
---
5) Triangle
- Base = 10 cm, Height = 9 cm
- Same formula:
$$
\text{Area} = \frac{1}{2} \times 10 \times 9 = 45\, \text{cm}^2
$$
✔ Answer: 45 cm²
---
6) Triangle
- Base = 7 cm, Height = 11 cm
- Area:
$$
\text{Area} = \frac{1}{2} \times 7 \times 11 = 38.5\, \text{cm}^2
$$
✔ Answer: 38.5 cm²
---
7) Triangle (with slanted height)
- Base = 8 cm, Height = 14 cm (the perpendicular height is shown)
- Use the same formula:
$$
\text{Area} = \frac{1}{2} \times 8 \times 14 = 56\, \text{cm}^2
$$
✔ Answer: 56 cm²
---
8) Trapezium (Trapezoid)
- Parallel sides: 4 cm and 8 cm
- Height = 10 cm
-
Area of a trapezium = $\frac{1}{2} \times (\text{sum of parallel sides}) \times \text{height}$
$$
\text{Area} = \frac{1}{2} \times (4 + 8) \times 10 = \frac{1}{2} \times 12 \times 10 = 60\, \text{cm}^2
$$
✔ Answer: 60 cm²
---
✔ Final Answers:
| Shape | Area |
|-------|------|
| 1) Square |
81 cm² |
| 2) Rectangle |
14 cm² |
| 3) Triangle |
16 cm² |
| 4) Triangle |
30 cm² |
| 5) Triangle |
45 cm² |
| 6) Triangle |
38.5 cm² |
| 7) Triangle |
56 cm² |
| 8) Trapezium |
60 cm² |
---
🔍 Summary of Formulas Used:
-
Square: $ \text{side}^2 $
-
Rectangle: $ \text{length} \times \text{width} $
-
Triangle: $ \frac{1}{2} \times \text{base} \times \text{height} $
-
Trapezium: $ \frac{1}{2} \times (a + b) \times h $, where $ a $ and $ b $ are the parallel sides
All calculations are correct and based on standard area formulas for 2D shapes.
Let me know if you'd like this as a printable worksheet or with diagrams labeled!
Parent Tip: Review the logic above to help your child master the concept of area of rectangles worksheet.
