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

 It is currently 18 May 2013, 14:18

# 2x + y = 12 |y| <= 12 For how many ordered pairs (x , y)

Author Message
TAGS:
Manager
Joined: 08 Aug 2008
Posts: 235
Followers: 1

Kudos [?]: 13 [0], given: 0

2x + y = 12 |y| <= 12 For how many ordered pairs (x , y) [#permalink]  10 Nov 2008, 05:20
2x + y = 12
|y| <= 12

For how many ordered pairs (x , y) that are solutions of the system above are x
and y both integers?
A. 7
B. 10
C. 12
D. 13
E. 14

I'm getting 13 as ans however not sure what ordered pairs mean..
no OE guys, lets discuss...
Manager
Joined: 30 Sep 2008
Posts: 114
Followers: 1

Kudos [?]: 7 [0], given: 0

Re: Ordered Pairs [#permalink]  10 Nov 2008, 05:34
|y| <= 12 <=> -12 <= y <= 12

2x + y = 12 => x = y/2 - 6, x is integer so y is even

=> y = -12, -10... , 8,10,12 => 13 possible y => 13 ordered pairs (x,y)
Manager
Joined: 14 Oct 2008
Posts: 160
Followers: 1

Kudos [?]: 17 [0], given: 0

Re: Ordered Pairs [#permalink]  10 Nov 2008, 06:10
Yup i am getting 13 as well. whats the QA ?
SVP
Joined: 17 Jun 2008
Posts: 1593
Followers: 7

Kudos [?]: 131 [0], given: 0

Re: Ordered Pairs [#permalink]  10 Nov 2008, 06:54
13 should be correct.
Re: Ordered Pairs   [#permalink] 10 Nov 2008, 06:54
Similar topics Replies Last post
Similar
Topics:
5 2x + y = 12 |y| <= 12 For how many ordered pairs (x 6 24 May 2007, 06:07
2x + y = 12 |y| <= 12 For how many ordered pairs (x , y) 7 30 Aug 2007, 20:56
2x + y = 12 |y| <= 12 For how many ordered pairs (x , 3 01 Nov 2007, 12:50
2x+y=12 IyI<=12 For how many ordered pairs (x,y) that are 5 11 May 2008, 06:14
6 For how many ordered pairs (x, y) that are solutions of the 9 14 Jan 2011, 16:40
Display posts from previous: Sort by