# Find the length and width of a rectangle

##### Question
Draw a rectangle that has a perimeter of 18 cm and an area greater than 18 sq.cm. What are the dimensions?

STEP 1:    It will be helpful if you can recall the basic properties of a rectangle. A rectangle is defined by the dimensions length and width. It has four sides, and also the opposite sides of a rectangle have the same length.

You are given the perimeter of a rectangle. The perimeter, as you know, is the total distance along the outside of the rectangle. The formula used to calculate perimeter is: In the formula, the variables l and w denote the length and width of the rectangle, respectively.

STEP 2:    Since you know the value of the perimeter, you can make the replacement in the formula. By dividing both the sides by 2, the equation changes to
9 = l + w, or l + w = 9.

STEP 3:    Think of the possible dimensions the rectangle can have if the sum of the length and width equals 9 cm. But, it is given that area of the rectangle has to be greater than 18 sq. cm. This means that the product of the length and width must be greater than 18.

Try different values for l and w such that the sum equals 9. Find the corresponding products, and then make a table of values. If you observe the table, then you can find that the area of the rectangle is greater than 18 only when the dimension of the rectangle is either 4 cm by 5 cm, or 5 cm by 4 cm.

STEP 4:    Choose any of the two desirable dimensions. Then, finally draw the rectangle. ### Comments for Find the length and width of a rectangle

Average Rating     Mar 03, 2018 Rating     Not Clear by: Anonymous Please make it more understandable. I didn't understand the table thing at all...

 Nov 14, 2017 Rating  Don’t insult my intelligence. by: Anonymous I have a problem that gives me the area, and only the area. I need to know how to find both length and width when neither are present and the only thing given to me is just the area. I already know these basics and I came here for help with more complicated problem that required something more than this basic formula.

 Nov 06, 2017 Rating well then by: charley not really helpful.. Sorry. .-.

 Sep 13, 2017 Rating     Mathematics master by: Anonymous No help ☹️

 Dec 22, 2016 Rating     boluwatifeasha@gmail.com by: ashaboluwatife please help me find the length of rectangle whose perimeter and area add me on boluwatifeasha@gmail.com

 Sep 08, 2016 Rating     8th grade problem by: Anonymous 8th grade math problem- a rectangle has an area of 90 units. what is the rectangles length and width?

 Sep 07, 2016 Rating     HELP 7TH GRADE IS HARD by: Anonymous Hi is there an easier way to solve this. I only have the area and need to find possible lengths and width. Thanks.

 Apr 08, 2016 Rating     Finding side length (Given Area) by: Anonymous Determine the value of L Area=9u2

 May 19, 2015 Rating     Area calculations by: Visual Math The formula for the area of a rectangle is A = w x l; if the area is given and the width is a fraction of the length, the formula can be expressed thus: A = (a/b x l) x l Since we are looking for the length, we invert the formula for the area of a rectangle: l = A/w Based on the information that the width is a fraction of the length, the formula would thus be in this form: l = A/(a/b x l) Now, let's rearrange the formula: l(a/b x l) = A l x a/b x l = A l^2 = A/(a/b) l^2 = Ab/a l = √(Ab/a) So, for example, if it is given that the area is given as 6cm^2, and the width is 2/3 of the length, then, using the formula above, we would get the following: l = 6/(2/3 x l) l(2/3 x l) = 6 l^2 = 6/(2/3) l^2 = 9 l = 3cm

 Feb 08, 2014 Rating     Area calculation by: Anonymous How do you find the length of rectangle if the area is given and the width is a fraction of the length?

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