Is d negative?
1. e+d=-12
2. e-d<12
Can someone please show me how to combine these two statements and arrive at the right answer? thanks.
Is d negative?
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okigbo wrote:Is d negative?
1. e+d=-12
2. e-d<12
Can someone please show me how to combine these two statements and arrive at the right answer? thanks.
-e -d = 12 AND 12 > e - d
-e - d > e -d
Add 'd' to both sides. Inequality should hold true.
-e > e
0 > 2e
0> e implies e is negative
Given that e + d = 12
'd' MUST be positive and greater than 12 to make this happen.
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I think it should be 'E'
Each statement is not sufficient alone. Combining both the statements we get -
e = -12 - d
-12 - d - d < 12
-2d < 24
-d < 12 -> d > -12
d could be anything.
Each statement is not sufficient alone. Combining both the statements we get -
e = -12 - d
-12 - d - d < 12
-2d < 24
-d < 12 -> d > -12
d could be anything.
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Correction:mridul_dave wrote:okigbo wrote:Is d negative?
1. e+d=-12
2. e-d<12
Can someone please show me how to combine these two statements and arrive at the right answer? thanks.
-e -d = 12 AND 12 > e - d
-e - d > e -d
Add 'd' to both sides. Inequality should hold true.
-e > e
0 > 2e
0> e implies e is negative
Given that e + d = 12
'd' MUST be positive and greater than 12 to make this happen.
Given that e + d = -12 and e is negative, depending value of e, d can be both positive and negative. Silly mistake of sign before 12.
Agree answer is E.
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okigbo wrote:Is d negative?
1. e+d=-12
2. e-d<12
Can someone please show me how to combine these two statements and arrive at the right answer? thanks.
1. d = -12-e. Insufficient unless we know whether e < -12
2. d > -12 + e. Insufficient
Combined: -12-d-d < 12
-24 < 2d
-12 < d. Insufficient
E is the answer
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please explain further.
adam15 wrote:I think C is the correct answer
1+2
yields e<0, and from 1 we know that e+d=-12 thus e+d<0 then d<-e since e<0 then d>0
any suggestions
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if e < 0 and d < -e, d could still be positive or negative.adam15 wrote:I think C is the correct answer
1+2
yields e<0, and from 1 we know that e+d=-12 thus e+d<0 then d<-e since e<0 then d>0
any suggestions
For example, if e=-5, we get d < -(-5) or d < 5, which could be positive or negative.
Back to the question:
1. e+d=-12
2. e-d<12
Assuming we all agree that they're not sufficient independently, let's jump right to combination.
Combined, we could pick e=-5 and d=-7, since:
-5 + (-7) = -12
and
-5 - (-7) = 2 < 12
Is -7 negative? YES
However, we can also pick e = -15 and d = +3, since:
-15 + 3 = -12
and
-15 - 3 = -12 < 12
Is +3 negative? NO
Since we can get both a YES and a NO answer, we don't have enough information to answer the question: choose E.
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from 1:
e = -12-d
from 2:
e-d<12
or, -12-d-d<12
or, -2d<24
or, -d<12
or, d>12
so d is not negative.
thus C is correct, which is the OA.
e = -12-d
from 2:
e-d<12
or, -12-d-d<12
or, -2d<24
or, -d<12
or, d>12
so d is not negative.
thus C is correct, which is the OA.
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When you did your last step, you forgot to add the negative sign:wanttobeat wrote:from 1:
e = -12-d
from 2:
e-d<12
or, -12-d-d<12
or, -2d<24
or, -d<12
or, d>12
so d is not negative.
thus C is correct, which is the OA.
-d < 12
becomes
d > -12
So, d could be either positive or negative... choose E.
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