Question

The width and the length of a rectangle are consecutive even integers. If the width is decreased by 3 inches, then the area of the resulting rectangle is 24 square inches. What is the area of the original rectangle?

Answer 1

The original are would be 48.

Since we know that the length and width are two consecutive even integers, we can model them as follows:

Width = x

Length = x + 2

This works because no matter what even number is put in for x, the length will also be even.

Now we know if we subtract 3 from the width, we have a new rectangle that gives us an area of 24 inches. Therefore, our new triangle has the following:

Width: x - 3

Length: x + 2

Area: 24

And we can plug this into the equation.

Length* Width = Area

(x + 2)(x - 3) = 24

x^2 - x - 6 = 24

x^2 - x - 30 = 0

This is not a quadratic that we can factor to show the following:

(x - 6)(x + 5) = 0

This gives us the answers of x = 6 and x = -5. Since a side can't be negative, we throw out the x = -5 and the answer is x = 6.

So if we go back to the original rectangle, we know:

Width = x = 6

Length = x + 2 = 8

Area = 6*8 = 48