Solution:
Steps to construct an angle of
105∘ :
1.Draw a ray PQ and draw an arc of some radius taking P as its centre, which intersects PQ at R.
2. Taking R as the centre and with the same radius as before, draw an arc intersecting the previously drawn arc at S.
[1 mark]
3. Taking S as the centre and with the same radius as before, draw an arc intersecting the arc at T ( see figure).
4. Taking S and T as the centre, draw an arc of the same radius to intersect each other at U.
[1 mark]
5. Join PU, let it intersect the arc at V. Taking T and V as the centre, draw arcs with radius more than
12TV. Let these arcs intersect each other at W.
6. Join PW which is the required ray that makes an angle of
105∘ with the ray PQ.
The angle so formed can be measured with the help of a protractor. It comes to be
105∘
[1 mark]