Problem. Through a given point (C) to draw a right line parallel to a given right line.
Sol.—Take any point D in AB. Join CD (Post. i.), and make the angle DCF equal to the angle ADC [xxiii.]. The line CE is parallel to AB [xxvii.].
Proposition 31
Problem. Through a given point (C) to draw a right line parallel to a given right line.
Sol.—Take any point D in AB. Join CD (Post. i.), and make the angle DCF equal to the angle ADC [xxiii.]. The line CE is parallel to AB [xxvii.].