I never liked wp's

the perimeter of a standard rug is 44ft the length is 2ft longer than the width find the dimensions width and length anyone please?

interval notation of the set {xl -2 > x > 6}

is it (-6 -2) ?

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- Apr 14th 2007, 09:33 PMrj2001word problem and interval notation
I never liked wp's

the perimeter of a standard rug is 44ft the length is 2ft longer than the width find the dimensions width and length anyone please?

interval notation of the set {xl -2 > x > 6}

is it (-6 -2) ? - Apr 14th 2007, 10:05 PMJhevon
Are you sure this is the right question? to have an interval for such a question, we need an inequality. there's no inequality here.

let width = x

=> length = x + 2

=> Perimeter = 2x + 2(x + 2) = 44

=> 2x + 2x + 4 = 44

=> 4x + 4 = 44

=> 4x = 40

=> x = 10

so the width is 10 and the length is 12

so the rug is a 10 x 12 rug

EDIT: oh, the interval thing is for the second question, ok i'll do that...what is xl? - Apr 15th 2007, 02:38 AMJhevon
ok, so {x| -2> x > 6} makes no sense. what you are actually saying is x is less than -2 but greater than 6. I think it should be {x| -2 < x < 6}, that is, x is greater than -2 but less than 6.

so in interval notation that would be (-2,6). we use parenthesis as oppsosed to square brackets since x cannot be equal to either of the values at the end points. - Apr 15th 2007, 06:46 AMSoroban
Hello, rj2001!

Is that interval problem stated correctly?

If it is, it'sthe way we should write it.*not*

Quote:

interval notation of the set {x l -2 > x > 6}

It says: x > 6 . (x is greater than 6)

. . and: -2 > x . (x is less than -2)

This is clearly impossible; a number cannot be greater than 6**and**less than -2.

The intent could have been: .x < -2 .**or**.x > 6

And the interval would be: .(-∞, -2) U (6, ∞)

- Apr 15th 2007, 08:04 AMrj2001
hi yeah sorry for not making it clear that was 2 problems in one post

but yeah the second one is on our online homework (mymathlab) multiple choice

Write interval notation for the set

{ x l -2 > x >-6 } the l = absolute value bar? but just one no close

answers are

(-6,-2)

[-6,-2]

[-6,-2)

(-6,-2]

this is a review from a chapter wayy back and I think he read it x is such that? something dunno if that will help - Apr 15th 2007, 10:33 AMjanvdl
x is between -2 and -6, but neither of the two numbers is included.

Which means that x is not equal to either -2 or -6, but lies between them.

For the rug:

Perimeter = 2L + 2B

But L = (x + 2)

B = (x)

44 = 2(x + 2) + 2(x)

44 = 4x + 4

x = 10

Thus B = 10

And L = 10 + 2 = 12