Home
Class 12
MATHS
Let ABCD be a quadrilateral with /CBD=2/...

Let `ABCD` be a quadrilateral with `/_CBD=2/_ADB, /_ABD=2/_CDB, AB=BC`, then

A

`AD=CD`

B

`/_ADB=/_CDB`

C

`/_CBD=/_ABD`

D

`/_ADC` is`(2pi)/3`

Text Solution

Verified by Experts

The correct Answer is:
A, B, C

`2x=/_CBD`
`2y=/_ABD`
In `/_\CBD`
`(sin(pi-(2y+x)))/(sinx)=(BD)/(BA)=(BD)/(BC)=(sin(pi-(2x+y)))/(siny)`
`impliessin(2+x)siny=sin(2x+y)sinx`
`=1/2[cos(y+x)-cos(3y+x)]=1/2[cos(x+y)-cos(3x+y)]`
`0ltx+y=1/2ABClt(pi)/2`
`0lt(3y+x)+(3x+y)lt2pi`
`=:. 3y+x=3x+yimpliesx=y`
`implies/_ABD=/_CBDimpliesAD=CD`
Promotional Banner

Similar Questions

Explore conceptually related problems

ABCD is a quadrilateral. Is AB+BC+CD+DA > AC+BD ?

Let ABCD be a cyclic quadrilateral such that AB=2, BC=3, angle B =120^(@) and area of quadrilateral =4sqrt3. Which of the following is/are correct ?

ABCD is quadrilateral. Is AB+BC+CD+DA < 2(AC+BD) ?

ABCD is a quadrilateral in which AB=BC and AD =CD ,Show that BD bisects both the angle ABC and angle ADC .

Let ABCD be a quadrilateral in which AB is parallel to CD and perpendicular to AD, AB = 3CDand the area of the quadrilateral is 4 square units. If a circle can be drawn touching all the sides of the quadrilateral, then its radius is:

In a quadrilateral ABCD, vec(AB) + vec(DC) =

If ABCD is a cyclic quadrilateral, then prove that AC.BD=AB.CD+BC.AD

Construct a quadrilateral ABCD with AB=3 cm, AB=3cm, AD=2.7 cm, DB=3.6 cm, angleB=110^(@) and BC=4.2 cm. Construct another quadrilateral A'BC'D' similar to quadrilateral ABCD so that diagonal BD'=4.8 cm.

ABCD is a quadrilateral in which AB||DC and AD = BC. Prove that angleA=angleB and angleC= angleD .

ABCD is a quadrilateral in which AD = BC. E, F, G and H are the mid-points of AB, BD, CD and AC respectively. Prove that EFGH is a rhombus.