Imagine a farmer trying to sell a piece of land that happens to be perfectly rectangular. The equation for calculating the area of a rectangle is as follows: area length × width. The solution to this sample problem means that the landscaper should build a pool that is 8 meters wide by 12 meters long. When the length and width of a rectangle are equal, the shape is a special case of a rectangle, called a square. If your rectangle happens to be a square, the two values of W will be equal, since the all of the sides of a square are equal. You will always get two values for W, the larger value is the length and the smaller value is the width. What should the width and length of the pool be? Using the method above, we haveĪt this point, you can use the quadratic equation to solve for W: The quantities P/2 and A are just numbers.Ī landscaper is building a rectangular pool and wants the pool to have an area of 96 square meters and a perimeter of 40 meters. Perfect! You now have a quadratic equation in the variable W. The trick is to solve the perimeter equation for L in terms of W and P, then substitute that expression in the area equation. We calculate the area of the rectangle by multiplying the width and height of the. This is enough to ensure that you arrive at a unique solution. In the given C program, we have given the width and height of a rectangle. However, since P and A are known values, you actually have two equations in two variables. (P = perimeter, A = area, W = width, and L = length.) At first glance, it may seem like there are too many variables to work with and no obvious quadratic equation. Start with two basic equations, P = 2W + 2L and A = WL. The Smiths plan to recarpet their family room, which measures 15 ft. The area of a desk top is 8 ¾ square feet. Find the length of a rectangle with area of 16 sq. Just select the first radio button and enter the area and perimeter. Find the area of a rectangle with length of 6 inches and width of 2 feet. If you're not too keen on solving equations, you can also use the calculator on the left. As it turns out, you can use quadratic equations to solve this type of geometric problem. However, a more challenging math problem is to do the opposite: compute the side lengths of a rectangle when you know the perimeter and area. When you know the width and length of a rectangle, you can easily calculate its perimeter and area. Which two rectangular measurements are known? Check radio button and enter values in the appropriate fields.