The legs form two altitudes = 5 and 12
The remaining altitude drawn from the right angle to the hypotenuse = (product of the legs) / hypotenuse =
(5 * 12) / 13 = 60/13 units
Sum of the altitudes = 5 + 12 + 60/13 = ( 17 * 13 + 60 ) / 13 = 151/13 units
