Question: What is the angle between the lines y = 2x + 1 and y = -1/2x + 3?
Options:
Correct Answer: 60 degrees
Solution:
The slopes are m1 = 2 and m2 = -1/2. The angle θ = tan^(-1) |(m1 - m2) / (1 + m1*m2)| = tan^(-1)(5/4) which is approximately 60 degrees.