Advertisements
Advertisements
Question
In the given figure, ABCD is a cyclic quadrilateral. If ∠BCD = 100° and ∠ABD = 70°, find ∠ADB.

Advertisements
Solution
It is given that ∠BCD = 100° and ∠ABD = 70°

We have to find the ∠ADB
We have
∠A + ∠C = 180° (Opposite pair of angle of cyclic quadrilateral)
So,
`angle A = 180° - 100°`
= 80°
Now in Δ ADB is `angle A ` = 80° and `angle ABD` = 70°
Therefore,
`angle A + angle ADB + angle ABD = 180°`
`80° + angleADB + 70° = 180°`
`angleADB = 180° - 150°`
= 30°
Hence, `angleADB` = 30°
APPEARS IN
RELATED QUESTIONS
Two tangents TP and TQ are drawn to a circle with centre O from an external point T. Prove that ∠PTQ = 2∠OPQ.

Fill in the blanks:
An arc is a __________ when its ends are the ends of a diameter.
If PA and PB are tangents from an outside point P. such that PA = 10 cm and ∠APB = 60°. Find the length of chord AB.
In the given figure, two tangents RQ, and RP and RP are drawn from an external point R to the circle with centre O. If ∠PRQ =120° , then prove that OR = PR + RQ.

In the given figure, common tangents PQ and RS to two circles intersect at A. Prove that PQ = RS.

AB and CD are common tangents to two circles of equal radii. Prove that AB = CD.
The figure given below shows a circle with center O in which diameter AB bisects the chord CD at point E. If CE = ED = 8 cm and EB = 4 cm,
find the radius of the circle.
The longest chord of a circle is __________
If d1, d2 (d2 > d1) be the diameters of two concentric circles and c be the length of a chord of a circle which is tangent to the other circle, then ______
A 7 m broad pathway goes around a circular park with a circumference of 352 m. Find the area of road.
