A DIYer has a question that involves geometry. He is cutting paneling to run along his stairs and is wondering if there is an easy way to calculate that angle.
Ellis Walentine: The easiest way is to run a very simple computation on a trig calculator. Actually, your computer probably has a trig calculator somewhere in the utilities folder. Just measure the rise and run between anytwo points on the slope. The quotient is the tangent of the included angle. Plug this into your calculator and it will tell you the precise angle (see drawing). The angle of your cuts on the bottom ends of your panel boards will be the complementary angle, or the difference between the included angles and 180 degrees.