Final answer:
To find the length of the rectangle with an area of 24 square centimeters and width of (a-5), solve the quadratic equation a^2 - 5a - 24 = 0, which gives a length a = 8 centimeters.
Step-by-step explanation:
The question asks us to find the length a of a rectangle that has an area of 24 square centimeters, given that the width is a-5. Since area of a rectangle is found by multiplying the length by the width, we can set up the equation a*(a-5) = 24. To find the value of a, we need to solve this quadratic equation.
First, we expand the equation:
a² - 5a = 24
Then, we set the equation to zero:
a² - 5a - 24 = 0
Next, we factor the quadratic equation:
(a - 8)(a + 3) = 0
There are two possible solutions for a:
Since a length cannot be negative, we discard a = -3 and conclude that the length a of the rectangle is 8 centimeters.