two circles intersects each other at A And E. Their common secant through E intersects the circle at points B and D. The tangent of the circle at points B and D intersect each other at point C. prove that ABCD is cyclic
Answers
this is your answer it may help you
Step-by-step explanation:
search-icon-header
Search for questions & chapters
search-icon-image
Question
Bookmark
In the given figure, two circles intersect each other at points A and E. Their common secant through E intersects the circles at points B and D. The tangents of the circles at points B and D intersect each other at point C. Prove that □ABCD is cyclic.
1854693
expand
Medium
Solution
verified
Verified by Toppr
It is given that two circles intersect each other at point A and E
Join AE,AB and AD
The angle between a tangent of a circle and a chord drawn from the point of contact is congruent to the angle inscribed in the arc opposite to the arc intercepted by that angle. BC is the tangent to the smaller circle and BE is the chord.
∴∠EBC=∠BAE.... (1)
Also, CD is the tangent to the bigger circle and ED is the chord.
∴∠EDC=∠DAE .....(2)
Adding (1) and (2), we get
∠EBC+∠EDC=∠BAE+∠DAE
⇒∠EBC+∠EDC=∠BAD.... (3)
In △BCD,
∠DBC+L∠BDC+∠BCD=180
o
..... (4) (Angle sum property)
From (3) and (4), we get
∠BAD+∠BCD=180
o
In quadrilateral ABCD,
∠BAD+∠BCD=180
o
Therefore, quadrilateral ABCD is cyclic. (If a pair of opposite angles of a quadrilateral is supplementary, the quadrilateral is cyclic)