It is currently 25 Sep 2017, 12:02

### 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

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

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# Problem set question from Manhattan 12th - newby question

Author Message
TAGS:

### Hide Tags

Intern
Joined: 19 May 2012
Posts: 28

Kudos [?]: 6 [0], given: 8

GMAT Date: 01-07-2013
GPA: 3.3
Problem set question from Manhattan 12th - newby question [#permalink]

### Show Tags

31 May 2012, 06:51
I've encounter a problem in GMAT Manhattan which I don't get.
Given that d/4 + 8/d + 3 = 0 , what is d?

In the solution they say you multiply the entire equation with 4d and thus come up with d^2 + 32 + 12d. But how? I can find how especially d4 can become d^2 by doing that.

Would like to know a solution step by step.

Last edited by jonatande on 31 May 2012, 07:09, edited 1 time in total.

Kudos [?]: 6 [0], given: 8

Math Expert
Joined: 02 Sep 2009
Posts: 41717

Kudos [?]: 124948 [2], given: 12079

Re: Problem set question from Manahttan - newby question [#permalink]

### Show Tags

31 May 2012, 07:02
2
KUDOS
Expert's post
jonatande wrote:
I've encounter a problem in GMAT Manhattan which I don't get.
Given that d/4 + 8/d + 3 = 0 , what is d?

In the solution they say you multiply the entire equation with 4d and thus come up with d^2 + 32 + 12d. But how? I can find how especially d4 can become d^2 by doing that.

Would like to know a solution step by step.

If you multiply $$\frac{d}{4} + \frac{8}{d} + 3 = 0$$ by $$4d$$ you'll get: $$\frac{d}{4}*4d + \frac{8}{d}*4d + 3*4d = 0*4d$$ --> $$d^2+32+12d=0$$ --> $$d=-8$$ or $$d=-4$$.

Hope it's clear.
_________________

Kudos [?]: 124948 [2], given: 12079

Intern
Joined: 05 Mar 2013
Posts: 25

Kudos [?]: 3 [0], given: 9

### Show Tags

23 Jun 2013, 06:56
In MGMAT Algebra, Quadratic Eqn, Problem Set - Page 62, Qn 2

Given that D/4 + 8/D + 3 = 0

What is D?

In solution he has multiplied 4d and got $$d^2+ 32 + 12 d$$ .. How come 32?

by taking LCM as 4D, Wont the Numerator become $$4 D^2 + 32 D + 12 D$$ or $$D^2 + 8D + 3D$$ ??

[Reveal] Spoiler:
OA : D = -8 / -4

Kudos [?]: 3 [0], given: 9

Math Expert
Joined: 02 Sep 2009
Posts: 41717

Kudos [?]: 124948 [0], given: 12079

### Show Tags

23 Jun 2013, 07:01
daisyhill1 wrote:
In MGMAT Algebra, Quadratic Eqn, Problem Set - Page 62, Qn 2

Given that D/4 + 8/D + 3 = 0

What is D?

In solution he has multiplied 4d and got $$d^2+ 32 + 12 d$$ .. How come 32?

by taking LCM as 4D, Wont the Numerator become $$4 D^2 + 32 D + 12 D$$ or $$D^2 + 8D + 3D$$ ??

[Reveal] Spoiler:
OA : D = -8 / -4

Merging topics. Please refer to the post above.

Hope it helps.
_________________

Kudos [?]: 124948 [0], given: 12079

Display posts from previous: Sort by