Questions: The length of a rectangle is 7 ft more than double the width, and the area of the rectangle is 99 ft^2. Find the dimensions of the rectangle.
Length: ft
Width: ft
Transcript text: The length of a rectangle is 7 ft more than double the width, and the area of the rectangle is $99 \mathrm{ft}^{2}$. Find the dimensions of the rectangle.
Length : $\square$ ft
Width : $\square$ ft
Solution
Solution Steps
Step 1: Define the Variables
Let the width of the rectangle be denoted as \( w \) (in feet). According to the problem, the length \( l \) can be expressed in terms of the width as:
\[
l = 2w + 7
\]
Step 2: Set Up the Area Equation
The area \( A \) of the rectangle is given by the product of its length and width. Therefore, we can write the equation for the area as:
\[
A = l \cdot w = 99
\]
Substituting the expression for length, we have:
\[
(2w + 7) \cdot w = 99
\]
Step 3: Solve the Equation
Expanding the equation gives:
\[
2w^2 + 7w - 99 = 0
\]
Using the quadratic formula or factoring, we find the solutions for \( w \):
\[
w = \frac{11}{2} \quad \text{or} \quad w = -9
\]
Since width cannot be negative, we take the positive solution:
\[
w = \frac{11}{2} \text{ ft}
\]
Step 4: Calculate the Length
Now, substituting the value of \( w \) back into the expression for length:
\[
l = 2 \left(\frac{11}{2}\right) + 7 = 18 \text{ ft}
\]