 everybody, myself P. V. Ekhande working as assistant professor in Department of Mechanical Engineering at Valchia Institute of Technology, Sulapur. Today we will see regarding the solving problems related to projections of planes in which we will consider the question where the figure for that certain part is given, the plane for that certain part is given and where to proceed for completing the answer and in that we need the knowledge related to the lines also. At the end of this session, the students will be able to draw the problems related to projections of planes when the data is given in the form of certain figure and then where to proceed for completing the answer with the knowledge of lines. So here we will take the question in which where to refer the figure which is given and where to complete the projections for the plane which is given in the figure is a parallelogram. A parallelogram is the figure or the plane with the corner positions A, B, C, D and for this A, B, C, D parallelogram where to complete its projections when the two lines are given to us. So line A, B in the front view that is A, B, F is given and A, H, B, H in the top view for that is known to us given to us and the other side that is A, D side in the front view and top view is known to us. Now as we know for the parallelogram when we consider the parallelogram for that parallelogram always two lines opposite to each other are with the same length and those are parallel to each other. When we consider for example A, B and C, D these are A, B and C, D is parallel to each other as well as those are with the same length. Where the other sides that is A, D and B, C are again parallel to each other and with the same length that comes at we are going to use over here and for using this concept for completing this figure we are going to use the knowledge of parallel lines also. In case of the parallel lines we know that the parallel lines projection will appear as a parallel in all the views in all views whether it is front view, top view, side view or any auxiliary view those will appear as parallel to each other and if the sides are same views will have sides are if suppose same then its projection in the views will be obtained with the same reduction or enlargement in the both figures. So here now we will consider the lines which are given in the question those are A, D and A, B. Now A, D line will have the parallelity with respect to B, C. So for completing B, C line over here where to draw the projection of B, C line from this B, F corner or B, H corner as a line parallel to A, D in the front view or A, D in the top view. So where to draw the line parallel so the parallelity with respect to this A, D line is to be maintained and on this line drawn will get the position of D point sorry C point similarly where to draw the line parallel to A, H, D, H from B, H in the top view. Now on these two lines we will obtain the third corner in the front view we will obtain the third corner over here somewhere here and in the top view we will obtain that corner somewhere here. Now for obtaining that third corner Cf again we will use the concept related to parallel lines in which the sides will appear as a parallel to each other. Now here A, B to that will have the parallelity of D, C line. So for completing the projection of that then where to complete the line starting from this D corner as a line parallel to A, B and which will have the intersection at this point and the corner is to be considered as a Cf corner. So that is the completion of parallelogram in the front view. In the same manner we can complete the parallelogram that figure in the top view by drawing now the line from this D H point as a line parallel to A, B that is A, H, B, H to this A, H, B, H where to draw line parallel to where to draw the line parallel from this D corner. So where to maintain the parallelity with this A, B and the line is to be completed in such a way that it will have the intersection with the line starting from B and the point will be obtained as C H and this is completion of the top view of the parallelogram and front view of the parallelogram. So in the question complete the projection means where to complete the front view and top view of the plane. Now is it clear to you that we are using the properties of lines parallel to each other means the knowledge of the projection of lines that is utilized in completion of problems related to the planes. So which concept we have considered over here related to the parallel lines correct that is lines will appear parallel in all the ways, two lines will appear parallel to each other in all the ways. So we are obtaining the parallelity of A D with C B over here, D C with A B over here. The same thing is in top view A B parallelity is with D C over here, A D parallelity is with B C over here. The reference taken is from ML Dabade. Thank you.