Look at a space, any space, whether it’s outside your house, inside or even somewhere else. Now draw a fence around that area you see, keeping the shape of that fence rectangular. You’ve successfully framed an area. A rectangle is a polygon, meaning a closed plane figure enclosed by lines on all sides. That’s as obvious as it can get! The same applies to a square.
Any shape can be used, but we’re gonna stick to square and rectangle here. If any of you out there thing there’s no difference between an area and a perimeter, think again. Look at it this way, for imagination’s sake: The length of the fence needed to close in that space you chose above is the perimeter, while the space inside it is the area. See, there’s a huge difference between the two. You can’t call an apple an orange just because they’re both fruits!
Perimeter is mathematically considered to be 1-dimensional. It shows all the typical states of being like this. Being 1-dimensional, it’s measurements are dealt in linear units such as inches, feet, or meters. Area, on the other hand, is 2-dimensional. It always possesses length and width. Measurements for it include square units—not linear units like used for the 1-dimensional perimeter—like square inches, square feet or square meters. Observe the word ‘square’ being so stubbornly appended to all the usual units. This is what distinguishes this measurement type so don’t forget to apply this simple addition.
Now, as with all things in Math, we’ll need to see it to believe it! Proof can only come in actual form, right? Not imagination, at least not if Math has any say in the matter. Exercises are what’s going to be provided below, so you get an idea of how to calculate the area of a square and a rectangle without getting it wrong.
For Rectangle: You know a rectangle has a length and a width. So, multiply the two of them (or get them married, as is better understood!).
A = L x W
For Square: A square is nothing but a rectangle having four equal sides, so to speak. So, multiply the length of one side by, well, itself.
A = s x s
Exercise 1: Find the area of a square with each side measuring 2 inches.
Answer: This is the classic, most basic, ‘area’ query in Math and you’ll see it everywhere. It’s used here to break the ice and get you to understand that the same logic you’re going to apply to this simple exercise is what’s supposed to go into others, no mater how complex.
A = s x s
A = (2 inches) x (2 inches) = 4 square inches (or) 4 in2.
Exercise 2: A rectangle has a length of 5 centimeters and a width of 6 centimeters. Find the area.
Answer: A = L x W
A = (5 centimeters) x (6 centimeters)
A = 30 centimeters (or) 30 cm2
That’s all there is to know about the basics of finding out the area of a square and a rectangle.