If you were to draw a line from the lower left corner, perpendicular to the two parallel lines, you would have a right triangle in which the 'near' side has length 220 cm and the hypotenuse has length 300 cm. Calling the angle, in the right triangle at that corner, , we have so that . That means that the angle between the diagonal and the new perpendicular is degrees. So you now have a right triangle in which that diagonal is the hypotenuse, the angle is degrees, and the "near" leg has length 220 cm.