3 (iii) Verify the following: (–1, 2, 1), (1, –2, 5), (4, –7, 8) and (2, –3, 4) are the vertices of a parallelogram.
Given A=(–1, 2, 1), B=(1, –2, 5), C=(4, –7, 8) and D=(2, –3, 4)
Given Three points A=(0, 7, –10), B=(1, 6, – 6) and C=(4, 9, – 6)
The distance between two points and is given by
The distance AB
The distance BC
The distance CD
The distance DA
Here As we can see
And
As the opposite sides of quadrilateral are equal, we can say that ABCD is a parallelogram.