If the image of the point `(2, 1)` with respect to a line mirror be `(5, 2),` find the equation of the mirror.

Explanation

Let` A=(2,1) & A′=(5,2)`

The line is mirror.

Line is perpendicular to AA′ and passes through the
midpoint.
Slope of AA′`=1/3`​

Slope of mirror=−3

Equation
`=(y−3/2)=−3(x−7/2​)`

`=>y−3/2​=−3x+1/(22)​`

`=>2y−3=−6x+21`

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