CBSE Class 10 Answered

AB and CD are the two  direct common tangents to the two circles.

Let the two tangent meet at an external point P.

Then, PA = PC .....(1) (tangents from an external point P are equal)

Also, PB = PD .........(2) (tangents from an external point P are equal)

Now, subtracting (2) from(1), we have

PA - PB = PC - PD

AB = CD

Similarly if the two tangents are transverse common tangent.

Then we will need to add the two tangents to the two given circles to get the required result.

Please revert back if you don't get the answer.