BREAKING: Target Test Prep releases Brand New 2026 On Demand GMAT prep course

Redeem

X-5=?

This topic has expert replies
Post new topic Post Reply
Previous Topic Next Topic
Master | Next Rank: 500 Posts
Posts: 265
Joined: Tue Jul 03, 2012 11:04 pm
Followed by:6 members

X-5=?

by grandh01 » Wed Aug 15, 2012 4:48 pm
If (x - 1)^2 = 400, which of the
following could be the value of x - 5?
(A) 15
(B) 14
(C) -24
(D) -25
(E) -26

OA is C
Top
Source: — Problem Solving |
Master | Next Rank: 500 Posts
Posts: 363
Joined: Sun Oct 17, 2010 3:24 pm
Thanked: 115 times
Followed by:3 members

by theCEO » Wed Aug 15, 2012 5:29 pm
grandh01 wrote:If (x - 1)^2 = 400, which of the
following could be the value of x - 5?
(A) 15
(B) 14
(C) -24
(D) -25
(E) -26

OA is C
a^2 = 400
a = 20 or -20
if a =20, x-1= 20 --> x = 21 and x-5 = 16
if a =-20, x-1= -20 ---> x = -19 and x-5 = -24
ans = c
Top
Post new topic Post Reply
• Page 1 of 1