Let's solve each triangle's area step by step using the formula:
>
Area of a triangle = ½ × base × height
We’ll go through each part (a to f) one by one.
---
a.
Given:
- Base = 4 cm
- Height (h) = 6 cm
$$
\text{Area} = \frac{1}{2} \times 4 \times 6 = 12 \, \text{cm}^2
$$
✔ Already solved in the image:
12 sq cm
---
b.
Given:
- Base = 6 cm
- Height (h) = 8 cm (shown as dotted line from top vertex to base)
$$
\text{Area} = \frac{1}{2} \times 6 \times 8 = 3 \times 8 = 24 \, \text{cm}^2
$$
✔ Answer: 24 sq cm
---
c.
Given:
- Base = 8 cm
- Height (h) = 9 cm (dotted line perpendicular to base)
$$
\text{Area} = \frac{1}{2} \times 8 \times 9 = 4 \times 9 = 36 \, \text{cm}^2
$$
✔ Answer: 36 sq cm
---
d.
Given:
- Base = 10 cm
- Height (h) = 6 cm (dotted line from top vertex to base)
$$
\text{Area} = \frac{1}{2} \times 10 \times 6 = 5 \times 6 = 30 \, \text{cm}^2
$$
✔ Answer: 30 sq cm
---
e.
Given:
- Base = 6 cm
- Height (h) = 7 cm (dotted line from top vertex to base)
$$
\text{Area} = \frac{1}{2} \times 6 \times 7 = 3 \times 7 = 21 \, \text{cm}^2
$$
✔ Answer: 21 sq cm
---
f.
Given:
- Base = 6 cm
- Height (h) = 6 cm (dotted line from top vertex to base)
$$
\text{Area} = \frac{1}{2} \times 6 \times 6 = 3 \times 6 = 18 \, \text{cm}^2
$$
✔ Answer: 18 sq cm
---
✔ Final Answers:
| Part | Area |
|------|------|
| a | 12 cm² |
| b | 24 cm² |
| c | 36 cm² |
| d | 30 cm² |
| e | 21 cm² |
| f | 18 cm² |
---
🔍 Explanation:
The key idea is that
the height must be perpendicular to the base. In all these triangles, the height is given as a dotted line from the opposite vertex to the base, forming a right angle — so we can directly use it.
Always remember:
>
Area = ½ × base × height
Just plug in the values and calculate!
Let me know if you'd like this explained with diagrams or more examples! 😊
Parent Tip: Review the logic above to help your child master the concept of triangle worksheets.
