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Making Two-dimensional Shapes

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Aligned To Common Core Standard:

Grade 1 - 1.G.2

What Are Two-dimensional Shapes? From your water bottle to your bedtime storybook, you are surrounded by objects of different shapes and sizes. Understanding the types of shapes is the most basic step in learning geometry. Two-dimensional shapes are the ones that have a length and breadth but no depth. A 2D shape can have any number of sides, and each side can either be a straight line or a curved line. All 2D shapes are polygons except for circles and ellipses. The basic two-dimensional shapes include; Circle- It is a closed 2D shape which has a center. The distance of the center to any point on the edge of the shape is equal and known as the radius. Triangle- It is a three-sided triangle that has three sides with three vertices. The sum of all internal angles of a triangle is equal to 180°. There are three types of triangles, including equilateral, scalene, and isosceles. Square- It is a four-sided 2D shape that has four equal sides. All angles in a square are at 90°, and even the diagonals bisect each other at 90°. Rectangle- It is a four-sided shape with equal opposite sides. All angles in this shape are equal to 90°. Other 2D shapes include pentagons, octagons, and hexagons. All of these have more than four sides.