Question

Jugue pont 1 ersection to the collakus
4.
If a line intersects two concentric circles (circles
with the same centre) with centre O at A, B, C and
D, prove that AB=CD (see Fig. 12.25).​

Answer 1

Step-by-step explanation:

construct perpendicular from o to bc.

and name the intersection m.

and we know perpendicular from center divides the chord into 2 equal parts so,

bm=mc let it be eq 1 also am=md let it be eq 2

on subtracting equation 1 from 2 get

am-bm=md-mc

which is equal to

AB=CD

hence proved.