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

Redeem

What is x?

Expert replies
by VJesus12 » Thu May 03, 2018 10:48 am

Timer

00:00

Answers

A

B

C

D

E

Stats

Difficulty

What is x? $$\left(1\right)\ \ \sqrt{4x}=6$$ $$\left(2\right)\ x^2=81$$ The OA is the option A.

Why is not sufficient the second statement? Any help?
Join the discussion
Source: — Data Sufficiency |

by Jay@ManhattanReview » Thu May 03, 2018 6:57 pm
VJesus12 wrote:What is x? $$\left(1\right)\ \ \sqrt{4x}=6$$ $$\left(2\right)\ x^2=81$$ The OA is the option A.

Why is not sufficient the second statement? Any help?
The second statement is not sufficient because of x^2 = 81 implies x = ±9. x can be either +9 or -9. No unique value. In the first statement, x cannot be negative, else the square root of 4x would be an imaginary number.

Hope this helps!

-Jay
_________________
Manhattan Review GMAT Prep

Locations: New York | Hyderabad | Mexico City | Toronto | and many more...

Schedule your free consultation with an experienced GMAT Prep Advisor! Click here.
Join the discussion