Question 1055024
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a rectangle has a perimeter of 6x^3+9x^2-10x+5 and a length of x. Find the width of the rectangle when the length is 21 inches.
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According to the condition, the perimeter of the rectangle is 

P = 6*21^3 + 9*21^2 - 10*21 + 5 = 59330 in.

Distract the doubled length (2*21 in) from the perimeter and divide the result by 2, and you will get the width.
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The solution by "josgarithmetic" is incorrect.


He simply didn't give the labor to himself to read and to understand the condition.