Look around yourself. How many objects with four sides and a closed shape can you find? All these objects you have identified are nothing but what we call “quadrilateral” in mathematical language. So, conceptually, a quadrilateral is any closed polygon with four sides. These two-dimensional figures can either be regular (congruent sides are equal) or irregular (congruent sides are unequal).
Numerous things in this world carry the shape of a quadrilateral. In fact, quadrilaterals are fundamental geometric shapes that find their application in engineering, architecture, and several other spheres. They are commonly used in making floor plans for commercial and residential spaces, company logos, graphic art, web designing, and more.
While board games and manipulatives make learning geometry fun and interesting, real-life examples help us understand how math and this world are interconnected. In this write-up, we have enlisted a bunch of real-life examples to give a clearer picture of how quadrilaterals shape the world around us. But first, let’s understand the unique properties that make a quadrilateral what it is.
Quadrilateral: Types and common properties
A quadrilateral is not one single geometrical figure. It is, in fact, a group of different four-sided figures having unique properties of their own but which fall in the same category of quadrilaterals because they have a few things in common. Different types of quadrilaterals include square, rectangle, rhombus, parallelogram, trapezium, and kite, and their typical properties are:
- They all have four sides, four vertices, and four angles.
- The sum of their interior angles is 360 degrees.
- They all have two diagonals.
- Adding the four sides of a quadrilateral will give its perimeter.
Real-life examples of quadrilaterals around us
Do you have a table in your bedroom? If not, go check out your dining table. Does the tabletop have a square or a rectangle shape? If yes, the tabletop is a quadrilateral, as squares and rectangles fall in this category.
2. Books and notebooks
Being a student, your bag and study table must be full of books. Pick any one of them and observe its shape. Most books and notebooks are rectangular, a shape that is also quadrilateral. You may also find some books in square forms, especially the ones for little kids. These, too, are examples of quadrilaterals.
3. Picture frames
Picture frames make awesome wall décor items. They enhance the beauty of a space and give it a personal touch with beautiful memories of family and friends. But have you noticed that these are also quadrilaterals that make an eye-catching geometric collage when arranged in a specific pattern?
Doors are usually the same everywhere with a fixed rectangular design unless, of course, it is a piece of art meant to have a unique and innovative design. So, no matter where you are, a door will always be a quadrilateral.
5. Baseball diamond
Love playing or watching a game of baseball? If yes, the baseball diamond, which is a quadrilateral, would have indeed caught your eye. The square-shaped field has equal sides measuring 90 feet, and all its internal angles are 90 degrees. Besides being an example of a real-life quadrilateral, a baseball diamond is an excellent resource for teaching area, perimeter, and other math concepts to students.
6. Road signs
Although road signs come in different shapes, such as circles and octagons, many are quadrilaterals with four sides, like a diamond and a rectangle. Did you know the shape of a road sign also holds significance? Rectangular (with the longer side vertical) and square signs usually convey traffic regulations, whereas diamond-shaped signs indicate warnings.
A chessboard is a game of intelligence and is loved by many. The gameboard has eight rows, eight columns, and 64 squares. Chessboard, as a whole, and its individual black and white sections forming a chequered pattern are real-life examples of squares and are also quadrilaterals.
8. Playing cards
Who doesn’t love to spend time playing cards with family and friends? No matter which card game you’re playing, you will have a few quadrilaterals at your disposal. Why do we say that? Because almost all card games are played with a pack of rectangular cards. So, the next time you play “go fish” or “crazy eight”, don’t forget to appreciate this real-life example of quadrilaterals.
9. Electronic devices
The fact that we are constantly surrounded by real-life quadrilaterals becomes even more evident when we take this next example on our list. Cell phones, laptops, and television are things we cannot imagine our lives without in today’s world. And guess what? These are quadrilaterals as well!
Windows opening up to reveal a beautiful view are always a favorite. Interestingly, windows are quadrilaterals as well. Doesn’t matter if it is a small window at the cozy corner of a wall or a large one making the space look open and airy; it will fall within the realm of this interesting geometrical shape.
11. Currency notes
Another example of real-life quadrilaterals is currency notes. All countries have their own currency notes with varied patterns, designs, and colors. But one thing that’s common among them all is the shape. Currency notes are always rectangular in shape. So, ask your parents to give you one-dollar, ten-dollar, fifty-dollar, and hundred-dollar bills to see the commonalities and what sets them apart.
12. Swimming pool
Swimming pools come in various designs, but standard swimming pools are usually rectangular, which is a quadrilateral. What’s more? Even the swimming pool tiles are quadrilaterals as they are square or rectangular in shape.
Colorful kites flying high in the sky are a mesmerizing sight. And we all have positive childhood memories of flying kites with our dads on a bright sunny day. But how many of you considered kites as quadrilaterals gliding in the sky? It’s only natural to not have thought this way, but now that you know, this will definitely strike your mind the next time you go kite-flying.
Most pillows we use to sleep on are quadrilaterals. Leaving aside the designer pillows you place on the couch or bed for decorative purposes, the ones we use to lay our heads on to get a good night’s sleep also belong to this group.
15. Hammered dulcimer
Another type of quadrilateral that we can find around us is a trapezoid. A trapezoid is also a quadrilateral with four sides, two parallel, and two non-parallel. In addition to other real-life examples of a trapezoid is a hammered dulcimer. It is a percussion-stringed instrument that looks like a quadrilateral and is widely played in Iraq, Iran, India, and many other parts of the world, including the UK and the US.
Isn’t it interesting to see how mathematical ideas and concepts you learn in class are applied to build the world around us? By recognizing and understanding these four-sided figures, not only will you deepen your understanding of geometry and its applications, but you’ll be able to appreciate the diverse shapes and forms present in our surroundings too!
We hope the examples shared above have given you a fair idea of how real-life objects can resemble a quadrilateral. So, take a moment and visually explore architecture, designs, and the vast expanse of nature. You’ll be able to spot more quadrilateral-like items if you take a closer look at your surroundings.