Question

Is there a triangle whose sides have lengths 10.2 cm, 5.8 cm, and 4.5 cm?

Answer 1

Suppose such a triangle is possible.
Then the sum of the lengths of any two sides would be greater than the length of the third side.
4.5 + 5.8 >10.2
5.8 + 10.2 > 4.5
10.2 + 4.5 > 5.8
Therefore, the triangle is possible.