Name the type of quadrilateral formed, if any, by the following point, and give reasons for your answer (4, 5), (7, 6), (4, 3), (1, 2)
Solution
Let the points (4, 5), (7, 6), (4, 3), and (1, 2) be representing the vertices A, B, C, and D of the given quadrilateral respectively.
`:.AB = sqrt((4-7)^2+(5-6)^2) = sqrt((-3)^2+(-1)^2) = sqrt(9+1) = sqrt10`
`BC =sqrt((7-4)^2+(6-3)^2) = sqrt((3)^2+(3)^2) = sqrt(9+9) = sqrt18`
`CD = sqrt((4-1)^2+(3-2)^2) = sqrt((3)^2+(1)^2) = sqrt(9+1) = sqrt10`
`AD = sqrt((4-1)^2+(5-2)^2) = sqrt((3)^2+(3)^2) = sqrt(9+9) = sqrt18`
Diagonal AC =`sqrt((4-4)^2+(5-3)^2) = sqrt((0)^2+(2)^2) = sqrt(0+4) = 2`
Diagonal CD =`sqrt((7-1)^2 + (6-2)^2) = sqrt((6)^2+(4)^2) = sqrt(36+16) = sqrt52 = 13sqrt2`
It can be observed that opposite sides of this quadrilateral are of the same length. However, the diagonals are of different lengths. Therefore, the given points are the vertices of a parallelogram.