Complete the solution of the problem from On Triangles discussed in the text of finding two sides AB, AG, of triangle ABG given that BG = 20, the perpendicular AD = 5, and the ratio AB : AG = 3 : 5, or, equivalently, that AB=3/5 AG (see Fig. 13.13) The Pythagorean Theorem enables us to express both AB and AG in terms of x.