Basic geometry

Get up to speed on the core foundations of geometry.
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Area and perimeter

Area and perimeter help us measure the size of 2D shapes. We’ll start with the area and perimeter of rectangles. From there, we’ll tackle trickier shapes, such as triangles and circles.
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Area and perimeter of polygons

Let's now extend our understanding of area to triangles and more interesting quadrilaterals! Common Core Standard: 6.G.A.1

Area and circumference of circles

You already know about area and perimeter of lots of shapes. Now we'll round out those concepts by applying them to circles. Mathematicians call the distance around a circle its circumference and the space inside a circle its area. In this tutorial, we'll learn that there's another type of pi in the math world, and it's even more awesome than apple pie. We'll use pi to find the circumference and area of any circle in the world, no matter how big or how small! Common Core Standards: 7.G.B.4

Scale drawings

Now that you understand lines, you can put lines together to create drawings. A scale drawing depicts an actual object that has been reduced (or enlarged) by a certain amount. The "scale" shows the relationship between those two sizes. After this set of tutorials, you can draw your bedroom "to scale" and practice rearranging your furniture!