how to construct an angle of measure 150 degrees???......
Here are the steps to construct an angle of measure 150°.
Step 1: Draw a line l and mark a point P on it. Now taking P as centre and with a convenient radius, draw a semi-circle which intersects line l at Q and R.
Step 2: Taking R as centre and with the same radius as before, draw an arc intersecting the previously drawn arc at S.
Step 3: Taking S as centre and with the same radius as before, draw an arc intersecting the arc at T (see figure).
Step 4: Taking T and Q as centre, draw arcs of same radius to intersect each other at U.
Step 5: Join PU which is the required ray making 150° with line l i.e. ∠UPR = 90°.
Hope! This will help you.