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605-655 (Medium)|   Geometry|      
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Bunuel
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If DA = DB, CD = CB and AB = AC, then x= 09 Jul 2021, 01:30
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A
Be sure to select an answer first to save it in the Error Log before revealing the correct answer (OA)!

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45% (medium)

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67% (02:28) correct 33% (02:34) wrong based on 90 sessions

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If DA = DB, CD = CB and AB = AC, then x=

A. 180/7
B. 30
C. 240/7
D. 36
E. 270/7


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A
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sumitkrocks
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If DA = DB, CD = CB and AB = AC, then x= 09 Jul 2021, 02:18
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7x = 180
x = 180/7
(A) is the correct answer IMO


Bunuel

If DA = DB, CD = CB and AB = AC, then x=

A. 180/7
B. 30
C. 240/7
D. 36
E. 270/7


Project PS Butler


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If DA = DB, CD = CB and AB = AC, then x= 09 Jul 2021, 02:26
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Define angle BAC = x and angle BDC = y, and start labelling derived angles from these two variables.
Then, DBC = 180-2y = 180-(2x+y) = x+y (since AB = AC)
Therefore, y = 2x => 180 - 4x = 3x => x = 180/7 (A)
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If DA = DB, CD = CB and AB = AC, then x= 09 Jul 2021, 09:17
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Given,
DA = DB, CD = CB and AB = AC
We need to find value of x.
DA = DB
which implies angle DBA = x (isosceles triangle)
Now in triangle BDA,
x+x+ ADB = 180
ADB = 180 - 2x
angle BDC = 2x (supplementary angle)

Now in triangle BDC,
2x + 2x + BCD = 180
BCD = 180 -4x

Also given
AB = AC
angle ABC = angle ACB
3x = 180 -4x
7x = 180
x = 180/7

IMO A
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If DA = DB, CD = CB and AB = AC, then x= Updated on: 09 Jul 2021, 10:40
Originally posted by zanto on 09 Jul 2021, 09:33.
Last edited by zanto on 09 Jul 2021, 10:40, edited 1 time in total.
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I have listed the steps in the picture attached. Choice A
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TarunKumar1234
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If DA = DB, CD = CB and AB = AC, then x= 09 Jul 2021, 10:17
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As, 180-p = 180- 2x or, p = 2x

So, x+ (x+2x) + (x+2x) = 180 or, x = 180/7.

I think A. :)
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If DA = DB, CD = CB and AB = AC, then x= 09 Jul 2021, 11:58
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this Q. is an application of the following two theorems:
1: Angles opposite to equal sides in a triangle are equal.
2: Exterior angle is equal to the sum of interior opposite angles


I hope the rest is easy to solve !!!! check the solution image uploaded by zanto.
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If DA = DB, CD = CB and AB = AC, then x= 10 Jul 2021, 06:20
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IMO A,

Post making all the angles in ABC interms of x , We know sum of angles is 180

Hence x is 180/7.

Posted from my mobile device
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If DA = DB, CD = CB and AB = AC, then x= 17 Mar 2023, 03:55
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