Want to learn how to tackle those tough MATHCOUNTS and AMC counting and probability problems? Check out Art of Problem Solving's Introduction to Counting & Probability by David Patrick.
Let be a right-triangle with . Let and be the midpoints of the legs and , respectively. Given and , find .
Solution
Let and . By the Pythagorean Theorem, and We wish to find . So, we add the two equations, multiply by , and take the squareroot to get
Want to learn how to tackle those tough AMC/AIME/Olympiad counting and probability problems? Check out Art of Problem Solving's Intermediate Counting & Probability by David Patrick.