The measures of two sides of a triangle are 5.2 and 8.1. Determine the range of values for the third side of the triangle.

In any triangle, the length of any side must be greater than the positive difference of the lengths of the other two sides, and less than the sum of the lengths of the other two sides.

Therefore, the range of values for the third side of the triangle is:
5.2 - 8.1 < third side < 5.2 + 8.1

-2.9 < third side < 13.3

So, the range of values for the third side of the triangle is -2.9 to 13.3.