Question: What is the angle between the lines y = 2x + 1 and y = -0.5x + 3?
Options:
Correct Answer: 90 degrees
Solution:
The slopes are m1 = 2 and m2 = -0.5. The angle θ is given by tan(θ) = |(m1 - m2) / (1 + m1*m2)| = |(2 + 0.5) / (1 - 1)|, which is undefined, indicating 90 degrees.