If x and y are positive and sqrtx = y, which of the following must be equal 0?
A) x-y
B) x- sqrty
C) y-2x
D) y- x^2
E) y^2 -x
If 13≤31-2x≤39, which of the following represents all possible values of x?
(A) -9≤x≤4
(B) -4≤x≤4
(C) -4≤x≤9
(D) 9≤x≤22
(E) 22≤x≤35
How should I go about doing this question, and what’s the quickest way? Thanks for your help!
Which of the following must be negative whenever x>y>0?
A) x^2 -4xy + y^2
B) x^2 -2xy – y^2
C) x^2 – xy -2y^2
D) y^2 -x^2 -xy
E) y^2 -x^2 +xy
if x^2 – y^2 = x- y and x<y, what is the average (arithmetic mean) of x and y?
A) 0
B) 1/2
C) 1
D) x/2
E) y/2
In a certain apartment building, residents are allowed to own exactly one dog, exactly one cat, or one dog and one cat. No other pets are allowed. There are 22 cats and 17 dogs in the building. If there are 25 apartments that contain only one dog or one cat, how many apartments, in total, contain pets?
(A) 27
(B) 32
(C) 35
(D) 39
(E) 42
Thank you. 🙂
Which of the following equations, together with 2x + y= 8, results in a system of equations with exactly one solution? A) -2x – y= -8 B) x+2y=0 C)2x+y=0 D) 2x+y=14 E) 4x+2y= 16
College Board released a bunch of sample questions this week for the new PSAT and SAT, which will make their debuts in October 2015 and March 2016, respectively. Over the next few days, I’ll be making posts working through each question, a few at a time, and commenting on them when I feel like I have (more…)
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