Three vertices of a parallelogram, taken in order, are (-1, -6), (2,-5) and (7,2). Write the coordinates of its fourth vertex.

Explanation

Let `{A}(-1,-6), {B}(2,-5), {C}(7,2)` and `{D}({x}, {y}).`


`AC `and `BD`are diagonals.



So, we know that the diagonals bisect each other in parallelogram, so the diagonals are divided in ratio `1: 1.`


Mid-point co-ordinates of` AC=` Mid-point co-ordinates of `BD.`
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