Geometry

Question Analysis:
This question involves using the Pythagorean Theorem to find a missing side length, then calculating the perimeter of a right triangle.  
The main focus is on combining geometric formulas with algebraic computation.

Key Concept Explanation:
The perimeter of any polygon is the sum of all its side lengths. For a right triangle:
1. First find all three sides using the Pythagorean Theorem (if necessary)
2. Then sum the side lengths

Step-by-Step Solution:
1. Given legs: 9 cm and 12 cm
2. Find hypotenuse:
 

Click "Show Answer" to reveal the answer and analysis