Area of a triangle
You learn to work out the area of a triangle.
How to work it out
- Calculate base × perpendicular height.
- Divide by 2 because the triangle is half of that rectangle.
A worked example
A triangle with base 6 cm and height 4 cm. What is the area?
- Use the formula: base times height divided by 2.
- 6 × 4 = 24.
- 24 ÷ 2 = 12.
- The area is 12 cm².
Another example
A triangle with base 10 m and height 5 m. What is the area?
- Work it out: 10 × 5 = 50.
- Divide by 2: 50 ÷ 2 = 25.
- The area is 25 m².
Watch out
You forget to divide by 2: the area is 24 instead of 12.
A triangle is half a rectangle. So divide by 2.
Tips
- The formula is: base × height ÷ 2.
- The height is measured straight up from the base, not along a slanted side.
Why it works
A triangle is exactly half of a rectangle with the same base and height. If the rectangle has area 6, the triangle is 3. The formula is: base times height divided by 2.