Question

# Is a triangle with sides of 5cm, 12cm and 15cm right?

Non-right triangles and trigonometry
Is a triangle with sides of 5cm, 12cm and 15cm right?

2021-09-01

Find out using the Pythagorean Theorem:
$$\displaystyle{a}^{{2}}+{b}^{{2}}={c}^{{2}}$$
Where c is the hypotenuse, and a & b are the cathituses. The hepotenuse is alwayse longer than each cathitus. So the 15cm side would be the hypotenuse in this instance.
Substitute:
$$\displaystyle{5}^{{2}}+{12}^{{2}}={15}^{{2}}$$
$$25+144=225$$
$$169=225$$
The Theorem doesn't apply, therefore this triangle isn't right.