prove that the line joining the mid-point of two equal chords of a circle subtends equal angles with the chord.

Explanation

Let AB and CD be the equal chords.

Let O be the center of the circle and Let M and N be the mid-points of the chords.

`therefore` `MB=AM`

`CN=DN`

Equal chords are equidistant from the center.

Now, OM=ON

In `triangleOAB` and `triangleOCD`

OA=OD (radius of the circle)

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