32) √(a²+8ab+16b²), a=3, b=-4

1. Recognize the expression under the radical as a perfect square: √((a+4b)²).
2. Simplify: |a+4b|.
3. Substitute a=3 and b=-4: |3 + 4(-4)| = |3 - 16| = |-13| = 13.