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So I need help with this problem, I’m new to polynomials. Can you also explain how to get the answer?

Find the polynomial that models the problem and use it to estimate the quantity:

A rectangle has a length of $x$ and a width of $5x^3 + 4 - x^2$. Find the perimeter of the rectangle when the length is 5 feet.

Fabio Lucchini
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reb error
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    Do you know the definitions of all the words (in particular: polynomial, Rectangle, length, width, perimeter) in the problem statement? – alphacapture Aug 19 '18 at 21:16
  • The perimeter of a rectangle is given by $2 \times (\mathrm{length} +\mathrm{width})$. Given $x = 5$ ft, you can use this to find to find the length and width. Then the aforementioned formula will give you the perimeter of the rectangle. – Nash J. Aug 19 '18 at 21:19

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The perimeter of a rectangle is $2($length$+$width$)$. Put the values of length and width. You'll get : Perimeter$=2×(x+5x^3+4-x^2)$. That's the polynomial of perimeter. Now put $x=5$, since the length$=5$. You'll get $2×(5+5×5^3+4-5^2) = 1218$. That's the required perimeter.

Anik Bhowmick
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