kuttingchai wrote:
Bunuel
what is the reason B must be true ???
the range is -2<x<7
A. x > 2 - no because x can be between -2<x<2
B. x > -7 -- the answer is true, is it because the values of x are always >-7
C. x< 2 - no because x can be between 2<x<7
D. -7 < x < 2 - no beacuse x can be between -7<x<-2 ????
E. none of the above. - i actually went for E answer choicein the another problem we had similar situation
ANY x from the ranges -1<x<0 and x>1 will definitely be more the -1. I didnot understood the reason there as well???
if-x-x-x-which-of-the-following-must-be-true-about-x-68886.htmlOption D is not correct since x could be 2<x<7. Otherwise your reasoning is correct.
We are given that
-2<x<7. The question is which of the following is true about
x?
x>-7 is true about
x, because as
x is more than -2 then it's definitely more than -7.
To elaborate more. Question uses the same logic as in the examples below:If x=5, then which of the following must be true about x: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.
Or:
If -1<x<10, then which of the following must be true about x:A. x=3
B. x^2=10
C. x<4
D. |x|=1
E. x<120
Again answer is E, because ANY
x from
-1<x<10 will be less than 120 so it's always true about the number from this range to say that it's less than 120.
Or:
If -1<x<0 or x>1, then which of the following must be true about x:A. x>1
B. x>-1
C. |x|<1
D. |x|=1
E. |x|^2>1
As
-1<x<0 or
x>1 then ANY
x from these ranges would satisfy
x>-1. So B is always true.
x could be for example -1/2, -3/4, or 10 but no matter what
x actually is it's IN ANY CASE more than -1. So we can say about
x that it's more than -1.
On the other hand for example A is not always true as it says that
x>1, which is not always true as
x could be -1/2 and -1/2 is not more than 1.
Hope it's clear.
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61% (01:18) correct
