📐 Part 1: Formula and Worked Examples

Triangle Area Formula: Area = ½ × base × height

Worked Example 1: A right-angled triangle has a base of 8 cm and height of 6 cm.
Area = ½ × 8 × 6 = ½ × 48 = 24 cm²

Worked Example 2: An equilateral triangle has a base of 10 cm and height of 8.7 cm.
Area = ½ × 10 × 8.7 = ½ × 87 = 43.5 cm²

✏️ Part 2: Practice Questions

1. Calculate the area of a right-angled triangle with base = 12 cm and height = 5 cm.

Answer: _______ cm²

2. A scalene triangle has a base of 15 cm and a height of 9 cm. What is its area?

Answer: _______ cm²

3. An equilateral triangle has a base of 14 cm and height of 12.1 cm. Find the area.

Answer: _______ cm²

4. Multiple Choice: What is the area of a triangle with base = 16 cm and height = 7 cm?

56 cm²

112 cm²

23 cm²

46 cm²

5. Draw a triangle in the box below and label its base and height. Then calculate its area if the base is 20 cm and height is 13 cm.

Answer: _______ cm²

6. A triangular garden plot has an area of 60 m². If the base is 15 m, what is the height?
Hint: Rearrange the formula to find height

Height = _______ metres

7. Challenge: Which triangle has the larger area?
Triangle A: base = 18 cm, height = 8 cm
Triangle B: base = 12 cm, height = 11 cm

Triangle _____ has the larger area of _______ cm²