Retired Moderator
Joined: 07 Jun 2014
Posts: 4812
Given Kudos: 0
WE:Business Development (Energy and Utilities)
Re: a > 0 || (–a – 10)(10 + a) || 10
[#permalink]
15 Apr 2018, 05:29
Explanation
Quantity A to find \(-10a - a^2 - 100 - 10a\), or \(-a2 - 20a - 100\).
Anything other than zero to an even power is positive, so \(-a^2\) is negative.
A negative number minus a positive number (20a) will remain negative.
A negative minus 100 will be even more negative.
So, Quantity A must be negative, and it must be less than Quantity B. The answer is choice (B).
Alternatively, plugging in a few positive values for a will give you, in the parentheses: (negative) times (positive) = negative for Quantity A, except if a = 10, which yields 0 for Quantity A. But Quantity A is still less than Quantity B.