Answer:
One of the angles in this triangle must be a right angle.
Step-by-step explanation:
Looking at the sides of the triangle, these work in the Pythagorean theorem:
10²+17.32² = 20²
100+299.9824 = 400
399.9824 = 400
The difference between the numbers is due to rounding. Since they work, this is a right triangle; one of the angles must be a right angle.