Final answer:
The value of x in the given rectangle is 13 feet.
Step-by-step explanation:
The area of a rectangle is given by the formula Area = Length × Width. In this case, we know that the area of the rectangle is 68 square feet and the length is x + 4 and the width is x - 9. Substituting these values into the formula, we get:
68 = (x + 4) × (x - 9)
Expanding the equation, we have:
68 = x² - 5x - 36
Now, rearranging the equation to form a quadratic equation:
x² - 5x - 104 = 0
Using the quadratic formula to solve for x:
x = (-b ± √(b² - 4ac)) / 2a
Substituting the values into the formula and simplifying, we get two possible values for x: x = 13 or x = -8.
However, since the dimensions of a rectangle cannot be negative, the only valid solution is x = 13.
Therefore, the value of x is 13 feet.