How to Describe a Street Sign in Geometry

Street signs may have a variety of geometrical forms.

While most American high-school students will be required to take at least one year of geometry classes, they can find this subject frustrating and often boring. Because of this, early introductions to the basic components of geometry, such as shapes, can help students succeed in their later studies. Furthermore, practical geometrical applications, such as the occurrence of geometrical shapes in everyday life, can also make the subject more accessible. To help your student understand geometry, work on describing a street sign in geometrical terms.

Instructions

1. Identify the shape. Most street signs will be rectangular; in some parts of the country they may be circular or triangular.

2. Discuss the perimeter of the street sign. If the sign is a rectangle, this will be the measurement of the base multiplied by two and added to the measurement of the height doubled; if it is a circle, it will be 2 * pi * r, with r being the radius of the circle. The perimeter of the triangle will be all three sides added together.

3. Find the area of the street sign. Talk with your child about how to find the area of a geometrical shape. The area of a rectangle is the base times the height; a triangle is half of the base times the height; the area of a circle is pi * (r^2), where r is the radius.

4. Introduce the concept of angles. Street signs can provide a basic demonstration of angles; point out to your child how the corners of a rectangular sign are all equal to 90 degrees, and have him calculate the total number of degrees in the shape (360). Similarly, a triangle will have 180 degrees, while a circle will have 360 degrees around its center.

References

• Slideshare: Geometric Shapes & Traffic Signs
• Pictures of Street Signs in the USA