An acute triangle is a triangle whose all interior three angles are less than 90 degrees. In most cases, the tip of the triangle aligns with the middle of the length opposite it.
Here is a good example of an acute-angled triangle.
As you can see, each of the angles measures 400, 650, and 750 respectively, which are all less than 900
The three angles of an acute-angled triangle should sum to 1800, courtesy of the Angle Sum Property i.e 400 + 650+ 750 = 1800.
When teaching the acute triangle concept to students (or any other type of triangle for that matter), it is important to provide them with some real-life examples. But what examples of acute triangles in real life can you give?
Well, there are several examples of acute triangles in real life—from everyday household items, animals, foods we eat, to tools in our garages. By and large, anything cut from an angle is likely to result in an acute triangle.
Without further ado, here are ten examples of acute triangles in real life.
1. A pizza pie
A pizza pie is cut at an acute angle. If you remove it from the rest of the pizza, it forms almost a perfect acute triangle.
A pizza can be cut into several acute triangle pies. You can also get the same effect with other pastries, such as pancakes that are made round.
2. Trusses of an A-frame House
The trusses of an A-frame house are constructed as acute triangular shapes. This is because triangles are rigid and strong enough to handle the compression forces from the roofing materials.
An assembly of triangles makes the long straight bars that form the truss. While other trusses are not acute triangles, their triangular shape creates a slope for draining water.
You can check trusses in any building under construction or one without a ceiling.
3. An alligator’s Mouth When Wide Open
An alligator is only able to open its mouth a few degrees. However, since it has a long mouth, it makes for an excellent acute triangle.
If you wish to see the acute angle, look at the alligator from a side and a contrasting background.
You will find that all the angles on the tips and edge of the throat are less than 900, and both jaws make for the long sides of the triangle.
4. Pyramids of Egypt
Pyramids of Egypt, or any pyramids for that matter, are acute triangles.
The great pyramids of Egypt were constructed thousands of years back as tombs for the kings. Their triangular shapes helped enhance their stability and ensured that they were not eroded by rainwater over the years.
If you cannot travel to Egypt to see the pyramids, buy any pyramid-shaped package and look at it from any side. It makes for a perfect acute triangle.
5. A pair of Scissors
A pair of scissors look like an acute angle when you open it up. None of the angles is greater than 900.
To give it a realistic triangular look, place the scissors on a contrasting background while open.
It creates a perfect acute triangle that you can see on the inside edges of the scissors.
You can create various triangle sizes by opening the scissors even more.
6. Spokes of Your Bicycle
The spokes of your bicycle make acute triangles between the center and the edges of the wheel.
The reasons for having an acute triangle are similar to those of the truss.
A triangle is able to handle compression forces better than any other shape. Therefore, it prevents the wheel from crumbling under pressure. A wheel has anything between 24 and 48 spokes.
7. A Divider
A divider is an instrument used to measure distances, mark them off, and transfer them to another platform.
It has two adjustable legs, which may be hinged together, and two sharp points.
You can adjust the distance between the two sharp points of the divider to create an acute triangle (especially if the divider is not hinged).
The divider gives a good view of the triangle when laid by the side.
8. Rewind, Play, and Fast-Forward Buttons of the Remote
The rewind button of the remote shows two triangles facing the left while fast forward shows the same facing the right.
On the other hand, the play button shows a single triangle facing the right.
All the three buttons are acute triangles drawn on the respective buttons.
You can also see the same replicated on your TV screen when you press any of the three buttons.
The old cassette players also have these triangles embedded into their play, rewind and fast-forward buttons.
9. Hedge Shears in Action
A pair of hedge shears opened up forms an acute triangle. They work similarly to a pair of scissors, only that they are larger and used for cutting shrubs and hedges.
You can adjust the blades to create different sizes of acute angles.
It is also possible to draw an acute angle with your shears by placing them on paper, drawing a line on the inside of the blades, and joining the tips with a straight line.
10. An Arrow Head and Iron Box
An arrowhead makes two acute triangles separated by the midrib. The entire arrowhead also makes one big acute triangle.
Its blades usually have tapered ends to beat the wind while traveling in the air and puncturing the target.
On the other hand, most iron boxes are triangular with an elongated front. They make a similar shape to an arrowhead, and all the angles are less than 90 degrees.
Closing Thoughts
There you have it; ten examples of acute triangles in real life. Since triangles are stable and strong, you will likely find many support and everyday items having an acute triangular shape.