Advertisements
Advertisements
प्रश्न
If ABCD is a cyclic quadrilateral in which AD || BC (In the given figure). Prove that ∠B = ∠C.

Advertisements
उत्तर
It is given that, ABCD is cyclic quadrilateral in which AD || BC
We have to prove `angleB = angle C`
Since, ABCD is a cyclic quadrilateral
So,
`angle B + angle D = 180°` and `angle A + angle C = 180°` ..… (1)
`⇒ angleB + angle A ` = 180° and `angle C + angle D = 180°` (Sum of pair of consecutive interior angles is 180°) …… (2)
From equation (1) and (2) we have
`angleB + angleD + angleB + angle A ` = 360° …… (3)
`angleA + angleC + angleC + angle D ` = 360° …… (4)
`2angleB + angleD + angleA = 2 angleC + angleA + angleD`
`2angleB = 2angleC`
`angleB = angleC`
Hence Proved
APPEARS IN
संबंधित प्रश्न
Two circles touch each other externally at P. AB is a common tangent to the circles touching them at A and B. The value of ∠ L APB is
(A) 30°
(B) 45°
(C) 60°
(D) 90°
In Figure 1, common tangents AB and CD to the two circles with centres 01and 02 intersect at E. Prove that AB = CD.

A circle touches the side BC of a ΔABC at a point P and touches AB and AC when produced at Q and R respectively. As shown in the figure that AQ = `1/2` (Perimeter of ΔABC).

In the fig. a circle is inscribed in a quadrilateral ABCD in which ∠B = 90° if AD = 23cm,
AB = 29cm and DS = 5cm, find the radius of the circle.
In the given figure, PQ is chord of a circle with centre O an PT is a tangent. If
∠QPT = 60°, find the ∠PRQ.

The radius of a circle is 6 cm. The perpendicular distance from the centre of the circle to the chord which is 8 cm in length, is
The length of three concesutive sides of a quadrilateral circumscribing a circle are 4 cm, 5 cm, and 7 cm respectively. Determine the length of the fourth side.
Draw a circle of radius 4.8 cm and mark its center as P.
(i) Draw radii PA and PB such that ∠APB = 45°.
(ii) Shade the major sector of the circle
From a point P which is at a distance of 13 cm from the centre O of a circle of radius 5 cm, the pair of tangents PQ and PR to the circle are drawn. Then the area of the quadrilateral PQOR is ______
From the figure, identify a sector.

