CLIMBER:'The angle within the triangle will be equal to 140 degrees minus 90 degrees, which equals 50 degrees. CLIMBER:'So I need to calculate the adjacent, which is equal to the opposite over tan.

A KS3 Bitesize 11-14 Maths guide on how to show the angles of a regular polygon equal 180° x (n-2). Constructions and loci Learn about constructions, loci and three-figure bearings with BBC ...