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The length of a rectangular garden is 6 feet less than 5 times its width. Its area is 235 square feet.

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3 votes

Answer:

Length = 31.4 ft

Width = 7.48 ft

Explanation:

Let's denote the width of the rectangular garden as
\sf w (in feet) and the length as
\sf l (in feet).

According to the given information:

The length is 6 feet less than 5 times the width:


\sf l = 5w - 6

The area of the rectangular garden is 235 square feet:


\sf \text{Area} = l * w


\sf 235 = (5w - 6) * w

Now, let's set up and solve the equation to find the values of
\sf w and
\sf l:


\sf 235 = (5w - 6) * w

Expand the equation:


\sf 235 = 5w^2 - 6w

Set the equation equal to zero:


\sf 5w^2 - 6w - 235 = 0

Now, we can either factor the quadratic equation or use the quadratic formula to solve for
\sf w.

Let's use the quadratic formula:


\sf w = (-b \pm √(b^2 - 4ac))/(2a)

For the given equation
\sf 5w^2 - 6w - 235 = 0, the coefficients are
\sf a = 5,
\sf b = -6, and
\sf c = -235.


\sf w = (-(-6 ) \pm √((-6)^2 - 4(5)(-235)))/(2(5))

Simplify the expression under the square root and calculate:


\sf w = (6 \pm √(36 + 4700))/(10)


\sf w = (6 \pm √(4736))/(10)


\sf w = (6 \pm 68.818602136341 )/(10)

This gives two potential values for
\sf w. However, since the width cannot be negative, we discard the negative solution:

So,


\sf w = (6 + 68.818602136341)/(10) \\\\ = (74.818602136341)/(10) \\\\ = 7.4818602136341 \\\\ = 7.48 \textsf{(in nearest hundredth)}

Now that we have the width
\sf w, we can find the length
\sf l using the relationship
\sf l = 5w - 6:


\sf l = 5(7.48) - 6 = 37.4 - 6 = 31.4

Therefore, the width of the rectangular garden is 7.48 feet, and the length is 31.4 feet.

User Jeff Hubbard
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