Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 29 Mar 2015, 11:35

# Update:

New questions posted on the CR forum and SC forum. Answer + Explanation = Kudos

### 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

# Is r^2 + s^2 = 0? (1) r + s = 0 (2) 3r^2 + 4s^2 = 0 17. If x

Author Message
TAGS:
Manager
Joined: 11 Jan 2007
Posts: 202
Location: Bangkok
Followers: 1

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

Is r^2 + s^2 = 0? (1) r + s = 0 (2) 3r^2 + 4s^2 = 0 17. If x [#permalink]  02 Aug 2007, 09:01
15. Is r^2 + s^2 = 0?
(1) r + s = 0
(2) 3r^2 + 4s^2 = 0

17. If x and y are positive integers and y = root (9-x) , what is the value of y?
(1) x <8> 1
_________________

cool

VP
Joined: 10 Jun 2007
Posts: 1465
Followers: 6

Kudos [?]: 128 [0], given: 0

Re: Equations [#permalink]  02 Aug 2007, 11:48
jet1445 wrote:
15. Is r^2 + s^2 = 0?
(1) r + s = 0
(2) 3r^2 + 4s^2 = 0

17. If x and y are positive integers and y = root (9-x) , what is the value of y?
(1) x <8> 1

For #15. It is B.
For r^2 + s^2 to be equal to 0, both must equal to zero. You can tell because both are positive numbers and if you add positive and positive and equal to zero, both must be 0.

(1) INSUFFICIENT. r=-4, s=4 works as well as both equal to 0.
(2) Same reason as above. SUFFICIENT.
Manager
Joined: 15 Aug 2006
Posts: 97
Followers: 1

Kudos [?]: 5 [0], given: 0

Yeah, I'd like it if you can post the other option.

based on what I see, it appears if 1 is sufficient, if you mean 1 is , x >1 and x <8> +/- 2 and since Y is said to be positive int, y value is 2.
_________________
GMAT Club Legend
Joined: 07 Jul 2004
Posts: 5079
Location: Singapore
Followers: 21

Kudos [?]: 180 [0], given: 0

Q1:
St1:
Case1: If r = 1/2, s = 1/2, then r^2+s^2 != 0
Case2: If r = 0, s = 0, then r^2+s^2 = 0.
Insufficient.

St2:
Case1: r=0, s=0, then r^2+s^2 = 0
Case2:If r = sqrt(3) and s = sqrt(4), then 3r^2 + 4s^2 = 0 but r+s !=0. Insufficient.

Using both st1 and st2:
Must be both r and s = 0. Sufficient.

Ans C

Q2:
Post Q2 again with HTML disabled.
Similar topics Replies Last post
Similar
Topics:
2 If p/3 = r/2 and r = 0.75s, what is the ratio of p to r to s 3 07 Jul 2013, 20:59
2 The integers r and s are distinct, r#0, and s#0. If r^2s^2 = 5 16 Sep 2010, 17:22
Is (1/p)>r/(r^2+2) (1) p=r (2) r>0 2 04 Apr 2007, 15:56
Is 1/p > r /r^2 + 2 1. p = r 2. r > 0 3 16 Dec 2006, 18:09
Is 1/p > r/(r^2 + 2) ? 1. p=r 2.r>0 9 08 Apr 2006, 10:54
Display posts from previous: Sort by