Q46. - Algebra 1

Question

Determine whether each set of measures can be the lengths of the sides of a right triangle.

12, 16, 21

Step-by-Step Solution

Answer

The given set of measures is not the lengths of the sides of a right triangle.

Step 1. Given.

The length of the triangle is $12,16,21$

Step 2. Determine how to identify whether the given measures are the sides of the right triangle, acute triangle, an obtuse triangle.

If c, is the longest side of the triangle, a and b are the other two sides of the triangle then:

(i) If $c^2<a^2+b^2$, then the triangle is acute.

(ii) If $c^2=a^2+b^2$, then the triangle is a right triangle.

(iii) If $c^2>a^2+b^2$, then the triangle is obtuse.

Step 3. Determine whether the given set of measures can be the lengths of the sides of a right triangle.

The triangle is having sides of measures 12, 16, and 21.

The longest side of the triangle is 21.

Therefore, the value c is 21.

Therefore, the values of a and b are 12 and 16 respectively.

 

Now, it can be obtained that:

$\begin{array}{c}{a}^2={12}^2=144\\ b^2={16}^2=256\\ c^2={21}^2=441\\ a^2+b^2=144+256=400\end{array}$

 

It can be noticed that:

$\begin{array}{c}{a}^2+b^2=400\\ a^2+b^2\ne c^2\end{array}$

As, $c^2\ne a^2+b^2$, therefore, the triangle is not a right triangle.

Therefore, the given set of measures is not the lengths of the sides of a right triangle.