Prove that the points (2,-1), (0,2), (2,3) and (4,0) are the coordinates other vertices of a parallelogram and find the angle between its diagonals.

Explanation

The points (2, -1), (0, 2), (2, 3) and (4, 0) are the coordinates of the vertices of a parallelogram

Let us assume the points,` A (2, − 1), B (0, 2), C (2, 3) and D (4, 0) `be the vertices.


Now, let us find the slopes
Slope of` AB = [(2 + 1) / (0 - 2)] = -3/2 `


Slope of `BC = [(3 - 2) / (2 - 0)] = 1/2 `


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