askvity

How to Calculate the Diagonal of a Square

Published in Geometry 2 mins read

The diagonal of a square can be calculated using the formula: d = a√2, where 'd' represents the length of the diagonal and 'a' represents the length of a side of the square.

Here's a breakdown of how to find the diagonal:

  • Understanding the Formula: The formula d = a√2 is derived from the Pythagorean theorem. A square's diagonal divides it into two right-angled triangles, where the diagonal is the hypotenuse and the sides of the square are the legs (a and b). Therefore, a² + a² = d², which simplifies to 2a² = d², and further to d = √(2a²) = a√2.

  • Knowing the Side Length: To calculate the diagonal, you need to know the length of one side of the square ('a').

  • Applying the Formula: Substitute the known side length ('a') into the formula d = a√2.

  • Calculating the Result: Calculate the value of a√2. You can either use a calculator to find the approximate value of √2 (approximately 1.414) or leave the answer in radical form (e.g., 5√2).

Example:

Let's say a square has a side length of 5 cm. To find the diagonal:

  1. Formula: d = a√2
  2. Substitute: d = 5√2
  3. Calculate: d ≈ 5 * 1.414 ≈ 7.07 cm

Therefore, the diagonal of the square is approximately 7.07 cm. You could also express it as 5√2 cm.

In summary, to find the diagonal of a square, simply multiply the length of one of its sides by the square root of 2 (√2).

Related Articles