GRE Prep Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
GRE Prep Club Team Member
Joined: 20 Feb 2017
Posts: 2506
Given Kudos: 1055
GPA: 3.39
In triangle ABC, AD = BD = DC (see figure). What is x?
[#permalink]
01 Mar 2021, 06:00
01 Mar 2021, 06:00
Expert Reply
2
Bookmarks
00:00
Question Stats:
90% (02:05) correct
10% (01:29) wrong based on 30 sessions
Hide Show timer Statistics
Attachment:
22.jpg [ 23.38 KiB | Viewed 2293 times ]
In triangle ABC, AD = BD = DC (see figure). What is x?
A. 4
B. 6
C. 8
D. 10
E. 12
Retired Moderator
Joined: 16 Apr 2020
Status:Founder & Quant Trainer
Affiliations: Prepster Education
Posts: 1546
Given Kudos: 172
Location: India
WE:Education (Education)
Re: In triangle ABC, AD = BD = DC (see figure). What is x?
[#permalink]
01 Mar 2021, 23:27
01 Mar 2021, 23:27
1
GeminiHeat wrote:
Attachment:
22.jpg
In triangle ABC, AD = BD = DC (see figure). What is x?
A. 4
B. 6
C. 8
D. 10
E. 12
Since, AD = BD = DC
We have 2 Isosceles triangles: BDC, BDA and 1 Equilateral triangle: ADC
In ADC: AD = DC
Angle DAC = Angle DCA = 60
So, Angle ADC = 60
Now, In BDC: BD = DC
Angle DCB = Angle DBC = 20
So, Angle BDC = 140
And, In BDA: BD = DA
Angle DBA = Angle DAB = x
Angle BDA = 360 - 140 - 60 = 160
i.e. 2x = 180 - 160 = 20
x = 10
Hence, option D
Re: In triangle ABC, AD = BD = DC (see figure). What is x?
[#permalink]
02 Mar 2021, 07:42
02 Mar 2021, 07:42
1
given
AD = BD = DC
so from △ADC ∠DAC=60
from △BDC ∠DBC=20
from △BDA ∠BAD=x
from △ABC ∠A=x+60
∠B=x+20
∠C=80
so ∠A+∠B+∠C=180
2x+160=180
x=10
option D is correct
AD = BD = DC
so from △ADC ∠DAC=60
from △BDC ∠DBC=20
from △BDA ∠BAD=x
from △ABC ∠A=x+60
∠B=x+20
∠C=80
so ∠A+∠B+∠C=180
2x+160=180
x=10
option D is correct
