Question

A student incorrectly determined that the length of DE is 29 cm explaining that 12-7 = 5 and 36-7 = 29 explain what mistake the student may have made and why this is not correct way to determine the length of a DE what is the actual length of DE

Answer 1

The length of the hypotenuse ≈ 39.7 cm

Step-by-step explanation:

Since the given triangle is a right-angled triangle, this means that we can apply the Pythagorean theorem.

The equation for Pythagorean calculation is:

(hypotenuse)² = (first leg)² + (second leg)²

In the given, we have:

first leg = 30 cm

second leg = 26 cm

Substitute with the givens in the above equation to get the hypotenuse as follows:

(hypotenuse)² = (30)² + (26)²

(hypotenuse)² = 1576

This means that:

either hypotenuse = √1576 = 39.69 ≈ 39.7 cm ..........> accepted

or hypotenuse = -√1576 = -39.69 ......> rejected as length can't be negative

Hope this helps :)