Q. 13.6( 8 Votes )

# What are the coordinates of the fourth vertex of the parallelogram shown on the right?

Answer :

Let the coordinate of fourth vertex be (x_{1}, y_{1}) and the point of intersection of diagonals be (x_{2}, y_{2})

Diagonals of a parallelogram bisects each other

According to the section formula for mid points

⇒ x_{2} = 3.5

y_{2}

⇒ y_{2} = 4.5

The point of intersection is (3.5, 4.5)

Again using the section formula for mid points

⇒ 1 + x_{1} = 7

⇒ x_{1} = 6

⇒ 1 + y_{1} = 9

⇒ y_{1} = 8

The fourth vertex of parallelogram is (6, 8)

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