Question

The area of a triangle is 280 cm². The ratio of its height to its base is 7:5. Find the length of its height (in cm)?

1. 32
2. 28
3. 20
4. 24

Answer 1

Correct Answer - Option 2 : 28

Given:

Area of triangle = 280 cm²

Ratio of height to its base = 7:5

Formula Used:

Area of triangle = ½ × Base × Height

Calculation:

Suppose, the base and height of the triangle is 5x and 7x, respectively.

Area of Triangle = ½ × 5x × 7x

⇒ 280 = ½ × 35x²

⇒ 35x² = 560

⇒ x² = 16

⇒ x = √16

⇒ x = 4

∴ The length of height of triangle = 7x = 28 cm