Part 2 of Proof of Heron's Formula, Perimeter, Area, and Volume, Geometry

Partners use materials to wrap three-dimensional objects to determine the formula for surface area. The groups use an orange to calculate the amount of peel it takes to completely cover the fruit. Using manipulatives, individuals then...

A triangle, square, hexagon, and circle all have a perimeter of one unit. Eighth graders must attempt to find the area of each and arrange them in order from least to greatest areas. A terrific task for applying four different...

Need an activity for teaching the Pythagorean Theorem? Geometry juniors apply the Pythagorean theorem to two triangles to determine a final calculation. 

Sliding over a corner makes a rectangle. The resource demonstrates why the formula of the area of a parallelogram works. As part of a larger playlist on basic geometry, the video works examples dealing with parallelogram areas.

Rectangles, parallelograms, and now trapezoids — so many quadrilaterals! Building on the previous lessons in the series, the video introduces the formula for the area of a trapezoid. The instructor shows images of trapezoids and...

Introducing the Heronês formula is the main objective of this lecture. Essentially, it describes how to solve a problem. Heron's formula is given, and then a problem is solved. Since the actual explanation of the formula will be given...

This video is the first installment in a series devoted to exploring Heron's Formula. It is a high-level experience that delves into proof using algebra. It demonstrates a step-by-step process for finding the area of a triangle using...

It's always nice to have a plan B. Pupils investigate an alternate formula for the area of a triangle that uses sine. A set of challenge questions shows how the new formula relates to the well-known formula of (1/2)bh.

The teacher explains how the formula for a triangle was determined. It is related to a parallelogram. What? The formula for the area of a triangle is derived from the area of a parallelogram? Seeing is believing, so watch this video to...

This modern animation and discussion of the ancient secrets of Pascal's triangle manages to be topical, engaging, and mathematically deep all at the same time. A great introduction to the power of number theory across multiple math...