X = 7, -3, 2
(x - 7)(x + 3)(x - 2) = 0
(x - 7)(x^2 + x - 6) = 0
x^3 - 6x^2 - 13x + 42 = 0
Absolute value of any number is always positive because it represent distance and distance will always positive.
To place chimney at least 30 feet , the distance along the width of the roof (x) will be x = 17.5 feet or x = 2.5 feet.
Since, The height of the roof is described by the function f(x)=−4/3|x−10| + 40
Since, minimum height is 30 feet.
So , substitute f(x)=30 in above expression.
30=−4/3|x−10| + 40
4/3|x−10| = 10
|x−10|=30/4
|x−10| = 7.5
Taking positive case,
x−10 = 7.5
x = 17.5 feet
Taking negative case,
x−10 = - 7.5
x = 10 - 7.5
x = 2.5 feet
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brainly.com/question/14473339
You have known the formula Length of base is la division of Area and a haft of the height.
So we have 3

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