Draw an angle of 70°. Make a copy of it using only a straight edge and compasses.

The below given steps will be followed to construct an angle of 70º measure and its copy.

(1) Draw a line l and mark a point O on it. Place the centre of the protractor at point O and the zero edge along line l.

(2) Mark a point A at 70º. Join OA. OA is the ray making 70º with line l. Draw an arc of convenient radius in the interior of 70º angle, while taking point O as centre. Let it intersect both rays of angle 70º at point B and C.

(3) Draw a line m and mark a point P on it. With the same radius as used before, again draw an arc while taking point P as centre. Let it cut the line m at point D.

(4) Now, adjust the compasses up to the length of BC. With this radius, draw an arc while taking D as centre, which will intersect the previously drawn arc at point E.

(5) Join PE. PE is the required ray which makes the same angle (i.e. 70º) with line m.