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In the shape of a rectangular prism has the dimensions shown. The

length, width, and height of the box.
(x + 6) in.
(x - 1) in.
(x - 2) in. the volume of the box is 60 cubuc inches

User Molmasepic
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1 Answer

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Answer: To find x, we can use the formula for the volume of a rectangular prism: V = lwh, where l is the length, w is the width, and h is the height.

Substituting the given dimensions, we have:

V = (x + 6)(x - 1)(x - 2) = 60

Expanding the product on the left side, we get:

V = (x^2 + 4x - 12)(x - 2) = 60

Multiplying out the right side, we get:

V = x^3 - 2x^2 + 4x^2 - 8x - 60 = x^3 + 2x^2 - 8x - 60

Combining like terms, we have:

x^3 + 2x^2 - 8x - 60 - 60 = 0

Simplifying, we get:

x^3 + 2x^2 - 8x - 120 = 0

Now we can use various methods to solve for x. One possible method is to use synthetic division with the possible rational roots of ±1, ±2, ±3, ±4, ±5, ±6, ±8, ±10, ±12, ±15, ±20, ±30, ±40, and ±60 (which are factors of the constant term 120) to narrow down the possibilities. Trying x = 2 as a root (since it is a factor of the constant term and also one of the dimensions of the prism), we get:

2 | 1 2 -8 -120

| 2 8 20

|--------------

| 1 4 0 -100

This means that x^3 + 2x^2 - 8x - 120 = (x - 2)(x^2 + 4x - 100), so the remaining quadratic factor can be factored as:

x^2 + 4x - 100 = 0

Using the quadratic formula, we get:

x = (-4 ± sqrt(4^2 - 4(1)(-100))) / (2(1))

x = (-4 ± sqrt(416)) / 2

x = (-4 ± 8sqrt(13)) / 2

x = -2 ± 4sqrt(13)

Since x represents a length, we discard the negative solution and conclude that:

x = -2 + 4sqrt(13)

Explanation:

User Abdelouahab Pp
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