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Use the given length and area of a rectangle to express the width algebraically. (Simplify your answer completely.)Length is 3x − 4Area is 6x^4 − 8x^3 + 9x^2 − 3x − 12

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Given the expression that represents the length of the rectangle:


3x-4

And the expression that represents the area of the rectangle:


6x^4-8x^3+9x^2-3x-12

You need to remember that the formula for calculating the area of a rectangle is:


A=lw

Where "l" is the length and "w" is the width.

If you solve for the width, you get this formula:


w=(A)/(l)

Therefore, you can write this expression to represent the width of the given rectangle:


(6x^4-8x^3+9x^2-3x-12)/(3x-4)

In order to simplify it, you can follow these steps:

1. Rewrite this term in this form in the numerator:


3x=-12x+9x

Then:


=(6x^4-8x^3+9x^2-12x+9x-12)/(3x-4)

2. Group pair of terms in the numerator and factor the Greatest Common Factor (the largest factor each group has in common) out of the parentheses:


=((6x^4-8x^3)+(9x^2-12x)+(9x-12))/(3x-4)
=(2x^3(3x-4)+3x(3x-4)+3(3x-4))/(3x-4)

3. Factor this Greatest Common Factor out in the numerator:


3x-4

You get:


=((3x-4)(2x^3+3x+3))/(3x-4)

4. By definition:


(a)/(a)=1

Therefore, you get:


=2x^3+3x+3

Hence, the answer is:


2x^3+3x+3

User Saikat Saha
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