To determine the range of possible lengths for the third side \( x \) of a triangle with side lengths of 5 and 8, we can use the triangle inequality theorem. According to this theorem, the sum of the lengths of any two sides of a triangle must be greater than the length of the third side.
We have three inequalities to consider:
- \( 5 + 8 > x \)
- \( 5 + x > 8 \)
- \( 8 + x > 5 \)
Now, let's solve each inequality one by one.
-
From \( 5 + 8 > x \): \[ x < 13 \]
-
From \( 5 + x > 8 \): \[ x > 3 \]
-
From \( 8 + x > 5 \): \[ x > -3 \quad (\text{This is always true if } x > 3) \]
Combining the valid inequalities, we find: \[ 3 < x < 13 \]
Thus, the range of possible lengths for \( x \) is:
- Lower bound: 3
- Upper bound: 13
So the final answer is:
3 and 13.