 Hi and welcome to our session. Let us discuss the following question. The question says show that the points A having coordinate 6, 2, D having coordinates 2, 1, C having coordinates 1, 5 and D having coordinates 5, 6 are the vertices of a square. Let's now begin with the solution. Let the vertices be given by having coordinates 6, 2, D having coordinates 2, 1, C having coordinates 1, 5 and D having coordinates 5, 6. The vertices of a square and only if D equal to BC is equal to CD is equal to DA. So in order to show that ABC and D are the vertices of a square, we have to show that AB is equal to BC is equal to CD is equal to DA. Now by the distance formula, we know that if coordinates of PR X1, Y1 and coordinates of QR X2, Y2 then distance between these two points that is PQ is given by cold square. Now by using this formula, AB is equal to square root X1 square and this is equal to, now we will find DA is equal to square root.