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Lesson 3: Properties of shapes

# Properties of shapes: FAQ

## What is the difference between classifying triangles by sides and by angles?

When we classify triangles by sides, we look at the lengths of the sides. For example, an equilateral triangle has three sides of equal length, while an isosceles triangle has two sides of equal length.
When we classify triangles by angles, we look at the size of the angles. For example, a right triangle has one right angle, while an acute triangle has three angles that are all less than $90$ degrees.
Try it yourself with this exercise:

## What is a quadrilateral and what are the different types of quadrilaterals?

A quadrilateral is a shape with four sides. There are many types of quadrilaterals, but some common ones include squares, rectangles, rhombuses, and trapezoids.
Try it yourself with these exercises:

## What is a property of a shape?

A property of a shape refers to a characteristic that the shape has. For example, a square has four sides of equal length, four right angles, and two sets of parallel sides. These are all properties of a square.
Try it yourself with this exercise:

## Why do we need to know about the properties of shapes?

There are many reasons we might want to know about the properties of shapes. For example, in architecture, we might want to design a building with certain shapes to make it aesthetically pleasing or structurally sound. In mathematics, understanding the properties of shapes can help us solve problems or prove theorems.