Paul and Alice leave Alice's house at the same time. Paul drives north and Alice drives west.

Question

Paul's average speed is 14mph slower than Alice's. At the end of one hour, they are 45 miles apart. Find Alice's average speed. (Round your answer to the nearest tenth.)

Answer 1

P=A-14

A^2 + (A-14)^2 = 45^2

2A^2 -28A = 2025-196

A^2 -14A = 1829/2

(A-7)^2 = 1829/2 + 49 = 1927/2

A = 7 + sqr(1927/2) = 7+ 31.04 = 38.04

Alice's speed = 38.04 mph