So we need to find the lenght of side a of a right triangle if we know b=13 and c=21 and c is the hypotenuse and we need to round the number to the nearest hundreth. So we can do that with Pythagorean theorem which states that: a^2 + b^2 = c^2. Now we simply put b^2 to the right side and find a^2 as: a^2=c^2 - b^2. Lets plug in the numbers and we will get a= sqrt (21^2 - 12^2)=16.492422. When we round it to the nearest hundreth a= 16.49.
