Solve the Problem $5 \mathrm {~m} 2 / \mathrm { s }$

question 216

Multiple Choice

Solve the problem.
-A piece of land is shaped like a right triangle. Two people start at the right angle of the triangle at the same time, and walk at the same speed along different legs of the triangle. If the area formed by the positions of the two people and their starting point (the right angle) is changing at $5 \mathrm {~m} 2 / \mathrm { s }$ , then how fast are the people moving when they are $4 \mathrm {~m}$ from the right angle? (Round your answer to two decimal places.)

• A) \(0.63 \mathrm {~m} / \mathrm { s }\)
• B) \(3.20 \mathrm {~m} / \mathrm { s }\)
• C) \(1.25 \mathrm {~m} / \mathrm { s }\)
• D) \(2.50 \mathrm {~m} / \mathrm { s }\)