dcastan2 wrote:
Bunuel wrote:
saxenagarima wrote:
If 4x-12 >= x + 9, which of the following must be true
a) X > 6
b) X < 7
C) X>7
D) X>8
E) X < 8
I doubt the OA in
MGMAT solutions
Given: \(4x-12\geq{x + 9}\) --> \(3x\geq{21}\) --> \(x\geq{7}\).
Only A is always true, as ANY \(x\) from the TRUE range \(x\geq{7}\) will be more than 6.
Answer: A.
Bunuel,
I must be reading the question incorrectly because I feel that after you get x>=7 you think 7=7 and 8>7 so the answer of x could 7 or 8 but since it is asking which is always greater than the answer would be D. 8. I don't see why we would look at it as x>6 when we solved the equation and got x>=7. How would the question need to be worded for that to be the case because I am really confused. I don't feel that in other
OG questions we we replaced the x with a number smaller when it is asking what number is greater than or equal to a number larger. If that's the case, that means C, D, and E were the trap answers? I'd appreciate your help. Thanks!
If , then which of the following must be true about :
A. x=3
B. x^2=10
C. x<4
D. |x|=1
E. x>-10
Answer is E (x>-10), because as x=5 then it's more than -10.
And for this one I know it can't be A-D, but for E, x could be -9 which wouldn't necessarily mean that it is greater than 5? Would you choose it anyways?
I think you are confused about what is given and what is asked.
Given that \(x\geq{7}\), so \(x\) is some number which is more than or equal to 7. Now, the question asks, what must be true about \(x\) (which we
know is more than or equal to 7).
If \(x\) is more than or equal to 7, then it must be true that \(x\) is greater than 6, thus A must be true.
The same with another example in your post: given that \(x=5\). The question asks, what must be true about \(x\). Since, \(x=5\), thus it's true to say that it's greater than -10.
Hope it's clear.
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