5-Day Free Trial
5-day free, full-access trial TTP
Available with Beat the GMAT members only code
MORE DETAILS
29-30
This topic has expert replies
-
magical cook
- Master | Next Rank: 500 Posts
- Posts: 484
- Joined: Sun Jul 30, 2006 7:01 pm
- Thanked: 2 times
- Followed by:1 members
-
radhika1306
- Master | Next Rank: 500 Posts
- Posts: 144
- Joined: Fri Apr 13, 2007 2:25 am
-
radhika1306
- Master | Next Rank: 500 Posts
- Posts: 144
- Joined: Fri Apr 13, 2007 2:25 am
Answer should be A.
(2x)^3 = 216
8*x^3 = 216
x = 3
Plug x into the equation and you have the answer.
Since statement 2 is a square, you will have two answers, with no way to distinguish between the two.
(In this case, the two answers are x = -6 or 3, but you don't actually need to solve this).
(2x)^3 = 216
8*x^3 = 216
x = 3
Plug x into the equation and you have the answer.
Since statement 2 is a square, you will have two answers, with no way to distinguish between the two.
(In this case, the two answers are x = -6 or 3, but you don't actually need to solve this).
-
magical cook
- Master | Next Rank: 500 Posts
- Posts: 484
- Joined: Sun Jul 30, 2006 7:01 pm
- Thanked: 2 times
- Followed by:1 members
-
agps
- Master | Next Rank: 500 Posts
- Posts: 101
- Joined: Tue Aug 07, 2007 1:45 am
- Followed by:1 members
In statement 1 I reached x=3 differently, but beny's way is faster.
anyway just as another possible way to get there, here it is:
2x^3=216
2x=6 (6*6*6=216, ending in 6 should be a good pointer 6*6=36*6=216, 6^x always ends in 6)
hence x=3.
anyway just as another possible way to get there, here it is:
2x^3=216
2x=6 (6*6*6=216, ending in 6 should be a good pointer 6*6=36*6=216, 6^x always ends in 6)
hence x=3.
