 Hello and welcome to the session. In this session we discussed the following question which says, construct an angle of 97.5 degrees with the help of ruler and compasses. Let's start with the solution. We will do this construction step by step. So here, the first step of construction would be, draw array OA. Now first we will draw an angle of 90 degrees. So we have drawn this array OA. Now in the next step, with OA center, use your table radius, draw an arc cutting at point P. So we have drawn this arc cutting the array OA at point P. Then in the next step, with P as the center and the same radius at the previously drawn arc at point C. So this arc cuts the previous arc at point C. Now in the next step, with C as the center and the same radius, cut the arc at point D. So this is the point D. Now our next step of construction is, with as the center and radius more than half of CD, draw an arc. So we have drawn this arc taking C as the center and radius more than half of CD. Now in the next step, we have with D as the center and the same radius, cut the previous arc. This point of intersection of the two arcs is the point E. We join OE. So we have got this angle AOE equal to 90 degrees. Next, taking the array OE, we will make an angle of 60 degrees at point O. So next step of construction would be, with as the center, these suitable radius draw an arc, the array OE at point Q. So we have drawn this arc taking O as the center and any suitable radius and this point of intersection of the arc and the array OE is point Q. Now in the next step, with Q as the center and the same radius, draw another arc to cut the previous arc point B. So we have drawn this arc intersecting the previous arc at point B. Then next, we join OB and produce it to intersect. So we get this angle is equal to 60 degrees. Now in the next step, we bisect the angle OE. To bisect the angle XOE, we take B and Q as the centers and radius more than half of BQ and we draw the arcs intersecting each other. So we have drawn these two arcs intersecting each other at point. Next, we join OR. We have joined OR and produced it to Y. So we get angle YOE equal to 60 degrees upon 2 that is equal to 30 degrees. Next, we bisect the angle YOE. So we have bisected the angle YOE and so we get angle ZOE equal to 30 degrees upon 2 which is equal to 15 degrees. Lastly, we will bisect the angle ZOE. So we have bisected the angle ZOE to get the angle A dash OE equal to 15 degrees upon 2 which is equal to 7.5 degrees. So we get angle A dash OE equal to 7.5 degrees and angle AOE is equal to 90 degrees. So this means that angle AOE plus angle A dash OE is equal to 97.5 degrees. Thus the required angle is angle A dash OE equal to 97.5 degrees. So this completes the session. Hope you have understood the solution of this question.