An acute triangle has sides measuring 10 cm and 16 cm. The length of the third side is unknown. Which best describes the range of possible values for the third side of the triangle?

A. [tex]x \ \textless \ 12.5 \text{ or } x \ \textgreater \ 18.9[/tex]
B. [tex]12.5 \ \textless \ x \ \textless \ 18.9[/tex]
C. [tex]x \ \textless \ 6 \text{ or } x \ \textgreater \ 26[/tex]
D. [tex]6 \ \textless \ x \ \textless \ 26[/tex]



Answer :

To determine the range of possible values for the third side of a triangle, it's important to apply the triangle inequality theorem. This theorem states that the sum of the lengths of any two sides of a triangle must be greater than the length of the third side. Let's denote the unknown third side as [tex]\( x \)[/tex].

Given the two sides of the triangle are 10 cm and 16 cm:

1. The first inequality: The sum of the lengths of the given sides must be greater than the length of the third side.
[tex]\[ 10 + 16 > x \][/tex]
Simplifying this, we get:
[tex]\[ 26 > x \quad \text{or} \quad x < 26 \][/tex]

2. The second inequality: The sum of the unknown side and the smallest given side must be greater than the length of the largest given side.
[tex]\[ x + 10 > 16 \][/tex]
Simplifying this, we get:
[tex]\[ x > 6 \][/tex]

3. The third inequality: The sum of the unknown side and the largest given side must be greater than the length of the smallest given side.
[tex]\[ x + 16 > 10 \][/tex]
This inequality simplifies trivially:
[tex]\[ x > -6 \][/tex]
Since [tex]\( x \)[/tex] is a length and must be positive, we don't need to consider this result specifically.

Combining the valid inequalities, we get:
[tex]\[ 6 < x < 26 \][/tex]

Thus, the range of possible values for the third side of the triangle is described by the inequality:
[tex]\[ 6 < x < 26 \][/tex]

So, the best description of the range of the possible values for the third side of the triangle is:
[tex]\[ 6 < x < 26 \][/tex]