Last visit was: 05 Sep 2026, 02:52 It is currently 05 Sep 2026, 02:52
Close
GMAT 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

we will pick new questions that match your level based on your Timer History

Track
Your Progress

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Close
Request Expert Reply
Confirm Cancel
User avatar
LordStark
User avatar
Current Student
Joined: 31 Aug 2016
Last visit: 30 Nov 2025
Posts: 287
Own Kudos:
1,210
 [10]
Given Kudos: 911
Status:Valar Dohaeris
GMAT 1: 700 Q49 V37
Products:
GMAT 1: 700 Q49 V37
Posts: 287
Kudos: 1,210
 [10]
Kudos
Add Kudos
10
Bookmarks
Bookmark this Post
Most Helpful Reply
User avatar
KarishmaB
Joined: 16 Oct 2010
Last visit: 04 Sep 2026
Posts: 16,643
Own Kudos:
81,179
 [5]
Given Kudos: 491
Location: Pune, India
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
Posts: 16,643
Kudos: 81,179
 [5]
4
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
General Discussion
avatar
src86
Joined: 14 Jul 2016
Last visit: 13 Aug 2021
Posts: 7
Own Kudos:
1
 [1]
Given Kudos: 5
Posts: 7
Kudos: 1
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
User avatar
chetan2u
User avatar
GMAT Expert
Joined: 02 Aug 2009
Last visit: 05 Sep 2026
Posts: 11,288
Own Kudos:
46,089
 [4]
Given Kudos: 339
Status:Math and DI Expert
Location: India
Concentration: Human Resources, General Management
GMAT Focus 1: 735 Q90 V89 DI81
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
GMAT Focus 1: 735 Q90 V89 DI81
Posts: 11,288
Kudos: 46,089
 [4]
1
Kudos
Add Kudos
3
Bookmarks
Bookmark this Post
PeepalTree
What is the area of the quadrilateral ABCD if BD=8, AB=6, and ED=5?

a. 10
b. 12
c. 14
d. 16
e. 18

Source:800 score


I am sure PeepalTree, you mean ABCE and not ABCD..
Now let's solve step wise..

Step I....
Take ∆ABD, a right angled triangle with sides in ratio 3:4:5 so AD = 2*5=10 or
\(AD^2=AB^2+BD^2=6^2+8^2=10^2......AD=10\)
Step II....
Take ∆s ABD and DEC..
AB and CE are perpendicular on BD..
So ABD and DEC are similar ..
Now ED:AD =5:10=1:2
So areas will be in ratio 1^2:2^2=1:4
Step III....
Now area of ∆ABD is AB*BD*1/2=8*6/2=24
Area of ∆DEC is 24*1/4=6.. rule of ratios of similar triangles
Area of quadrilateral / trapezium ABCE is area of ∆ABD-area of ∆DCE=24-6=18

E
avatar
src86
Joined: 14 Jul 2016
Last visit: 13 Aug 2021
Posts: 7
Own Kudos:
Given Kudos: 5
Posts: 7
Kudos: 1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Hi Chetan,
From Triangle ABD, AE = 5.
And since opp. angles in the quadrilateral are 90 degree each, I took AB=FC = 6 and E as the mid pt. (based on the figure). Is this incorrect approach ?

Also I figured Triangle ABD and DEC are similar,

CE/AB = DE/AD

Therefore CE =3 and it satisfies the mid pt. assumption.

Area of Quadrilateral ABCF = 6x4 =24 sq. units. and area of Triangle AEF = 6 sq. units.

Therefore, area of quad. ABCE = 24 -6 = 18 (E)
User avatar
chetan2u
User avatar
GMAT Expert
Joined: 02 Aug 2009
Last visit: 05 Sep 2026
Posts: 11,288
Own Kudos:
46,089
 [1]
Given Kudos: 339
Status:Math and DI Expert
Location: India
Concentration: Human Resources, General Management
GMAT Focus 1: 735 Q90 V89 DI81
Products:
Expert
Expert reply
Active GMAT Club Expert! Tag them with @ followed by their username for a faster response.
GMAT Focus 1: 735 Q90 V89 DI81
Posts: 11,288
Kudos: 46,089
 [1]
1
Kudos
Add Kudos
Bookmarks
Bookmark this Post
src86
Hi Chetan,
From Triangle ABD, AE = 5.
And since opp. angles in the quadrilateral are 90 degree each, I took AB=FC = 6 and E as the mid pt. (based on the figure). Is this incorrect approach ?

Area of Quadrilateral ABCF = 6x4 =24 sq. units. and area of Triangle AEF = 6 sq. units.

Therefore, area of quad. ABCE = 24 -6 = 18 (E)

No, you cannot take E as the midpoint unless it is clearly specified or you prove and then work ahead.
But a big NO to taking these estimates from the figures
User avatar
LordStark
User avatar
Current Student
Joined: 31 Aug 2016
Last visit: 30 Nov 2025
Posts: 287
Own Kudos:
Given Kudos: 911
Status:Valar Dohaeris
GMAT 1: 700 Q49 V37
Products:
GMAT 1: 700 Q49 V37
Posts: 287
Kudos: 1,210
Kudos
Add Kudos
Bookmarks
Bookmark this Post
chetan2u
PeepalTree
What is the area of the quadrilateral ABCD if BD=8, AB=6, and ED=5?

a. 10
b. 12
c. 14
d. 16
e. 18

Source:800 score


I am sure PeepalTree, you mean ABCE and not ABCD..
Now let's solve step wise..

Step I....
Take ∆ABD, a right angled triangle with sides in ratio 3:4:5 so AD = 2*5=10 or
\(AD^2=AB^2+BD^2=6^2+8^2=10^2......AD=10\)
Step II....
Take ∆s ABD and DEC..
AB and CE are perpendicular on BD..
So ABD and DEC are similar ..
Now ED:AD =5:10=1:2
So areas will be in ratio 1^2:2^2=1:4
Step III....
Now area of ∆ABD is AB*BD*1/2=8*6/2=24
Area of ∆DEC is 24*1/4=6.. rule of ratios of similar triangles
Area of quadrilateral / trapezium ABCE is area of ∆ABD-area of ∆DCE=24-6=18

E

thank you chetan2u sorry for the typo
User avatar
dave13
Joined: 09 Mar 2016
Last visit: 10 Jul 2026
Posts: 1,081
Own Kudos:
Given Kudos: 3,851
Posts: 1,081
Kudos: 1,161
Kudos
Add Kudos
Bookmarks
Bookmark this Post
PeepalTree


What is the area of the quadrilateral ABCE if BD = 8, AB = 6, and ED = 5? (Note: Figure not drawn to scale.)

A. 10
B. 12
C. 14
D. 16
E. 18


Source:800 score

Attachment:
img1.jpg


Area of rectangle = width * length = 4*6=24

Area of Right tringle = 3*4*1/2 = 6

Area of quadrilateral = 24-6 = 18
User avatar
Kinshook
User avatar
Major Poster
Joined: 03 Jun 2019
Last visit: 04 Sep 2026
Posts: 6,129
Own Kudos:
6,088
 [1]
Given Kudos: 164
Location: India
GMAT 1: 690 Q50 V34
WE:Engineering (Transportation)
Products:
GMAT 1: 690 Q50 V34
Posts: 6,129
Kudos: 6,088
 [1]
Kudos
Add Kudos
1
Bookmarks
Bookmark this Post
LordStark


What is the area of the quadrilateral ABCE if BD = 8, AB = 6, and ED = 5? (Note: Figure not drawn to scale.)

A. 10
B. 12
C. 14
D. 16
E. 18


Source:800 score

Attachment:
img1.jpg


Since triangles ABD & CDE are similar

and Since AD = 10 & ED = 5
EC = 3 and BC = 4

Area of quadrilateral ABCE = 1/2 (EC + AB)*BC = 1/2 (3 + 6) * 4 = 18

IMO E
User avatar
bumpbot
User avatar
Non-Human User
Joined: 09 Sep 2013
Last visit: 04 Jan 2021
Posts: 39,215
Own Kudos:
Posts: 39,215
Kudos: 1,157
Kudos
Add Kudos
Bookmarks
Bookmark this Post
Automated notice from GMAT Club BumpBot:

A member just gave Kudos to this thread, showing it’s still useful. I’ve bumped it to the top so more people can benefit. Feel free to add your own questions or solutions.

This post was generated automatically.
Moderator:
Math Expert
113150 posts