Intercept form x/a + y/b = 1 is ideal when both axis intercepts are given. Remember: a is x-intercept, b is y-intercept. Normal form xcos(alpha) + ysin(alpha) = p gives the line in terms of the perpendicular from origin: p is the perpendicular distance (always positive) and alpha is the angle the perpendicular makes with the x-axis. Normal form is crucial for problems involving distance from origin.