Answer:
1.88 inches
Step-by-step explanation:
The volume is the product of length, width, and height. If w represents the width of the box, then its length is 4w and its height is w+7. The volume is then ...
V = (4w)(w)(w+7)
We want to find the value of w that makes V=126. It is convenient to use the graphing calculator to look for zeros of a function, so we can write the equation as ...
V - 126 = 0
4w·w·(w+7) -126 = 0
The only positive solution to this equation is near w ≈ 1.883.
The width of the box is about 1.88 inches.
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Attached is output from the DESMOS free graphing calculator. The ALEKS calculator requires a subscription. The method of solution is substantially the same, but requires a little more work on the ALEKS calculator to find the zero-crossing.
