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Select the correct answer from each drop-down menu.Phyllis bought 21 feet of wood to frame a window. If she makes a triangular window, what is the greatest area the window can have?For a given perimeter, the triangle with the largest perimeter isv triangle. Using this type of triangle, the sides wouldmeasureSo, the greatest area the window could be is aboutsquare feet

Select the correct answer from each drop-down menu.Phyllis bought 21 feet of wood-example-1
User Roddick
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1 Answer

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Equilateral Triangles

An equilateral triangle has all of its three sides of the same measure. Suppose the side length of an equilateral triangle is L.

The perimeter of such a triangle is:

P = 3L

Phyllis bought 21 feet of wood to frame a triangular window. This corresponds to the perimeter of the triangle, so we can calculate the side length:

L = P/3

L = 21 feet / 3

L = 7 feet.

Now we know the length of the side of the triangle, we calculate the area by using the formula:


A=\frac{\sqrt[]{3}}{4}L^2

Substituting L = 7 feet:


\begin{gathered} A=\frac{\sqrt[]{3}}{4}(7ft)^2 \\ A=\frac{\sqrt[]{3}}{4}49ft^2 \\ \text{Calculating:} \\ A\approx21.22ft^2 \end{gathered}

User Anthony Cannon
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