This document discusses finding the angle of inclination and slope of a line, as well as the angle between two lines. It defines inclination as the angle measured counterclockwise from the x-axis to the line. Slope is related to inclination by the formula that if a non-vertical line has an inclination of θ and a slope of m, then tanθ = m. It also provides the formula for finding the angle between two non-perpendicular lines based on their slopes. Several examples are worked through to demonstrate finding inclination, slope, and the angle between lines.