Mathematics
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.
![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. NCERT Class 9 Mathematics CBSE Solutions.](https://cdn1.knowledgeboat.com/img/ncert-9/q4-ex-9-2-circles-maths-ncert-cbse-class-9-solutions-1118x871.png)
Circles
2 Likes
Answer
Draw a perpendicular from the center of the circle to the line AD, such that OM ⊥ AD
BC and AD are the chords of smaller circle and the bigger circle respectively.
![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. NCERT Class 9 Mathematics CBSE Solutions.](https://cdn1.knowledgeboat.com/img/ncert-9/q4-ex-9-2-circles-maths-answer-ncert-cbse-class-9-solutions-1132x870.png)
We know that,
Perpendicular from the center bisects the chord.
⇒ BM = MC ……… (1)
⇒ AM = MD ……… (2)
By subtracting equation (1) from (2), we get :
⇒ AM − BM = MD − MC
⇒ AB = CD
Hence, proved that AB = CD.
Answered By
1 Like
Related Questions
If two equal chords of a circle intersect within the circle, prove that the segments of one chord are equal to corresponding segments of the other chord.
If two equal chords of a circle intersect within the circle, prove that the line joining the point of intersection to the centre makes equal angles with the chords.
Three girls Reshma, Salma and Mandip are playing a game by standing on a circle of radius 5 m drawn in a park. Reshma throws a ball to Salma, Salma to Mandip, Mandip to Reshma. If the distance between Reshma and Salma and between Salma and Mandip is 6 m each, what is the distance between Reshma and Mandip?
A circular park of radius 20 m is situated in a colony. Three boys Ankur, Syed and David are sitting at equal distance on its boundary each having a toy telephone in his hands to talk each other. Find the length of the string of each phone.