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Vesnalui [34]
4 years ago
8

Which function models the area of a rectangle with side lengths of 2x – 4 units and x + 1 units? What is the area when x = 3?

Mathematics
1 answer:
evablogger [386]4 years ago
3 0

Answer:

D. f(x) = 2x^2 − 2x − 4; A = 8

Step-by-step explanation:

The area of a rectangle is given by the formula length x wide.

In this case we have that the length is 2x -4 and the wide is x +1

Therefore, the area will be:

A= (2x-4)(x+1)= 2x^2+2x-4x-4=2x^2-2x-4\\A= 2x^2-2x-4

Now, when x = 3 we would have:

A=2(3)^2-2(3)-4= 2(9)-6-4=18-10=8\\A=8

Thus, the right answer is D.

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Step-by-step explanation:

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Answer:

The given data is:

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S_{XY}=\frac{\sum_{i=1}^{n}(X_{i}-\bar{X})(Y_{i}-\bar{Y})}{n-1}

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