SOLUTION: Ana wants to build a wooden box with a square base and a height of 1 foot. Then she will paint the outer surface of the box. Ana has a small can of paint that will cover 30 square

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Question 1118664: Ana wants to build a wooden box with a square base and a height of 1 foot. Then she will paint the outer surface of the box. Ana has a small can of paint that will cover 30 square feet. The outer surface area of the box is given by the function f(x)=x^2+4x
A.What equation can you use to determine the dimensions of a box whose outer surface area is 12.square feet?
B.Find the length of the box by solving the equation you wrote in part a
C. Describe how you would solve the equation you wrote in part a using a graph
D. Suppose Ana wants to use all the paint she has what is the measure of the length of the base x of the largest box she can build
Answer by josgarithmetic(39617) About Me  (Show Source):
You can put this solution on YOUR website!
..., if the given 30 square feet for the paint, and if coating all of the FOUR sides and ONE ENTIRE BOTTEM (its bottom side), and box has no top, then, length of the bottom, as x, can be found:


(D)
x%2Ax%2B4x
x%5E2%2B4x
x%5E2%2B4x=30
x%28x%2B4%29=30, does not seem to be whole number factorization...
x%5E2%2B4x-30=0
x=%28-4%2B-+sqrt%2816%2B4%2A30%29%29%2F2
x=%28-4%2B-+sqrt%28136%29%29%2F2
x=%28-4%2B2%2Asqrt%2834%29%29%2F2
highlight%28x=-4%2Bsqrt%2834%29%29