GRE Prep Club Daily Prep
Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.
Customized
for You
Track
Your Progress
Practice
Pays
Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.
Which of the following must be even ?
[#permalink]
02 Apr 2024, 23:44
02 Apr 2024, 23:44
Expert Reply
00:00
Question Stats:
83% (01:34) correct
16% (01:25) wrong based on 6 sessions
Hide Show timer Statistics
Which of the following must be even ?
A. \(x^2+6x+9\)
B. \(x^2+7x+12
\)
C. \(x^2+4x-21\)
D. \(x^4+4x-12\)
E. \(x^2+8x+15\)
A. \(x^2+6x+9\)
B. \(x^2+7x+12
\)
C. \(x^2+4x-21\)
D. \(x^4+4x-12\)
E. \(x^2+8x+15\)
Manager
Joined: 11 Nov 2023
Posts: 228
Given Kudos: 78
WE:Business Development (Advertising and PR)
Re: Which of the following must be even ?
[#permalink]
11 May 2024, 19:59
11 May 2024, 19:59
1
With number property questions such as these, I "plug in" even and odd into the formulas.
odd*odd = odd, odd*even = even, even*even = even
and odd+odd = even, odd+even = odd, and even+even = even
e = even, o = odd
A)
x is even: \(e^2 + 6(e) + 9 = e + e + o = o\)
x is odd: \(o^2 + 6(o) + 9 = o + e + o = e\)
B)
x is even: \(e^2 + 7(e) + 12 = e + e + e = e\)
x is odd: \(o^2 + 7(o) + 12 = o + o + e = e\)
C)
x is even: \(e^2 + 4(e) - 21 = e + e - o = o\)
x is odd: \(o^2 + 4(o) - 21 = o + e - o = e\)
D)
x is even: \(e^4 + 4(e) - 12 = e + e - e = e\)
x is odd: \(o^4 + 4(o) - 12 = o + e - e = o\)
E)
x is even: \(e^2 + 8(e) + 15 = e + e + o = o\)
x is odd: \(o^2 + 8(o) + 15 = o + e + o = e\)
odd*odd = odd, odd*even = even, even*even = even
and odd+odd = even, odd+even = odd, and even+even = even
e = even, o = odd
A)
x is even: \(e^2 + 6(e) + 9 = e + e + o = o\)
x is odd: \(o^2 + 6(o) + 9 = o + e + o = e\)
B)
x is even: \(e^2 + 7(e) + 12 = e + e + e = e\)
x is odd: \(o^2 + 7(o) + 12 = o + o + e = e\)
C)
x is even: \(e^2 + 4(e) - 21 = e + e - o = o\)
x is odd: \(o^2 + 4(o) - 21 = o + e - o = e\)
D)
x is even: \(e^4 + 4(e) - 12 = e + e - e = e\)
x is odd: \(o^4 + 4(o) - 12 = o + e - e = o\)
E)
x is even: \(e^2 + 8(e) + 15 = e + e + o = o\)
x is odd: \(o^2 + 8(o) + 15 = o + e + o = e\)
gmatclubot
Re: Which of the following must be even ? [#permalink]
11 May 2024, 19:59
Moderators:
