quadratics

This topic has expert replies
Newbie | Next Rank: 10 Posts
Posts: 6
Joined: Sun Mar 20, 2011 8:44 am
Thanked: 1 times

quadratics

by prithviforever » Sun May 15, 2011 5:03 am
Think option(2) is sufficient. Not clear bout the first one..

If in the equation x2 - 2x - c = 10, x is a variable and c is a
constant, what is the value of c?
(1) (x + 3) is a factor of the equation x2 - 2x - c = 10.
(2) 5 is a root of the equation x2 - 2x - c = 10.


please help.
Source: — Data Sufficiency |

Legendary Member
Posts: 759
Joined: Mon Apr 26, 2010 10:15 am
Thanked: 85 times
Followed by:3 members

by clock60 » Sun May 15, 2011 5:21 am
i hope that 1 st is also suff
(1)if x+3-factor of x^2-2x-c=10, you can insert x=-3 in equation and obtain c=5
the same is true for st 2
simply insert x=5 in equation and got c=5
the answer looks like D