Constants

Problem Solving — algebra and arithmetic (GMAT Focus Edition)
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Constants

by rapper » Mon Oct 22, 2012 4:18 pm
If b, c, and d are constants and x2 + bx + c = (x + d)2 for all values of x, what is the value

of c?

(1) d = 3

(2) b = 6

Hi i got its answer as A.Is it correct?
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by \'manpreet singh » Mon Oct 22, 2012 7:48 pm
rapper wrote:If b, c, and d are constants and x2 + bx + c = (x + d)2 for all values of x, what is the value

of c?

(1) d = 3

(2) b = 6

Hi i got its answer as A.Is it correct?


Seems like you have forgot to put answer options?
kindly put the options then we can see.:)

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by rapper » Tue Oct 23, 2012 6:03 am
This a Data Sufficiency Question...So i think option are not required

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by rapper » Tue Oct 23, 2012 6:04 am
This a Data Sufficiency Question...So i think option are not required

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by \'manpreet singh » Wed Oct 24, 2012 7:53 pm
rapper wrote:If b, c, and d are constants and x2 + bx + c = (x + d)2 for all values of x, what is the value

of c?

(1) d = 3

(2) b = 6

Hi i got its answer as A.Is it correct?
x2 + bx + c = (x + d)2= x2 + d2+ 2dx

bx + c = d2 + 2 dx

c = x(2d-b) + d2

now moving to the statement I

d= 3 , we don't know the value of b --- Not Sufficient.

Statement 2,

b=6 , we don't the know value of d ----- Not Sufficient.


Taking both the statement together:b=3 and d=6

c = x(6-6) + 36
c=36 Suffcient

Answer is C

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by Jim@StratusPrep » Thu Oct 25, 2012 9:51 am
A is the correct answer, with d as 3 we can calculate be to be 6. You were correct.
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by \'manpreet singh » Thu Oct 25, 2012 8:10 pm
Jim@StratusPrep wrote:A is the correct answer, with d as 3 we can calculate be to be 6. You were correct.
Jim can you explain the answer?

Singh