one diameter of the circle circumscribing the rectangle ABCD is 4y=x+7.If the coordinates of A & B are (-3,4) &(5,4) respectively , find the equation of the circle.

Centre P of the circle lies on the line ...(1)

and perpendicular bisector of AB.

As AB is parallel to *x*-axis, therefore, perpendicular bisector of AB passes through and is parallel to *y*-axis. So, its equation is

*x = 1 ..*.(2)

On solving equations(1) and (2), we get

*x = 1, y = 2*.

Thus, the coordinates of centre P are *(1, 2)*.

radius = AP =

Hence, the equation of the circle is

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