Even though there is a wide variety of different triangles in the world, knowing a single equation allows us to find the area of each and every one of them. Follow along with this step-by-step presentation as Zoe clearly models how to...

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.

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...

Pupils figure out how to be resourceful when tasked with finding the area of a triangle knowing nothing but its endpoints. Beginning by exploring and decomposing a triangle, learners find the perimeter and area of a triangle. They...

Use a triangle area formula that works when the height is unknown. The eighth installment in a 16-part series on trigonometry revisits the trigonometric triangle area formula that previously was shown to work with the acute triangles....

What do you do when you don't think you have enough information? You look for another way to do the problem! Pupils combine what they know about finding the area of a triangle and trigonometry to determine triangle area when they don't...

What? The calculation of area is a linear distance? A short video shows how to use the areas of simple polygons to estimate the area under a graph. Pupils divide the area under a curve into figures to easier calculate the area. Given...

Scholars learn how to determine the area of compound shapes by finding the areas of the basic shapes that make it up. Pupils find the areas by adding areas together or subtracting them.

Young geometers and biologists investigate the math of nature in an activity that is just the bee's knees. Participants will study the tessellations of hexagons in a beehive, along with the natural rationale behind the specific shape....

Viewers learn how to apply proportional reasoning to find area of sectors and arc lengths with a video that starts off explaining how to find the areas of circle sectors and the lengths of arcs. Scholars then practice solving problems...

Scholars can use area formulas, but can they apply what they know about area? The lesson challenges learners to think logically while practicing finding area of shapes such as rectangles, circles, parallelograms, triangles, and other...

How many sides does that polygon have? Building directly from lesson number eight in this series, learners now find the area and perimeter of any polygon on the coordinate plane. They decompose the polygons into triangles and use Green's...

Find the area of triangles, rectangles, and parallelograms using this metric activity.

Use the area of polygons to calculate the area between curves. Pupils calculate areas under income and expense curves by filling the space with squares and right triangles. Using that information, they determine the profit related to the...

Unfortunately for young mathematicians, the world isn't made entirely of parallelograms, triangles, and trapezoids. After first learning the area formulas for these common shapes, students apply this new knowledge to...

Extend young mathematicians' understanding of area with a geometry lesson on trapezoids. Building on their prior knowledge of rectangles and triangles, students learn how to calculate the area of trapezoids and other...

Lateral area and surface area are simple concepts, but calculating them is not as easy! Using formulas, learners calculate lateral area and surface area for the same three-dimensional figures. The resource discusses the formula variables...

As they investigate scaling figures and calculate the resulting areas, groups determine the area of similar figures. They continue to investigate the results when the vertical and horizontal scales are not equal. 

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

Imagine a world built of triangles. A performance task asks scholars to consider just that. They use their knowledge of special segments of a triangle to make decisions about the area of triangular plots of land.

Not all structures take the shape of a polygon. The 21st lesson in a series of 29 shows young mathematicians they can create polygons out of composite shapes. Once they deconstruct the structures, they find the area of the composite figure.

Young mathematicians build an understanding of area and perimeter with their own two hands in a series of interactive geometry lessons. Through the use of different math manipulatives, children investigate the properties of...

You'd be surprised what you can do with a string! The constraint is the length of string, and the task is to maximize area. Given a series of composite shapes, learners must create a formula for the maximum area for a specified...

It's a piece of pizza! Pupils learn about a sector of a circle as a slice of the circle and determine how to find its area. Scholars continue to find out how to calculate the segment of a circle based on the sector's area. At the end,...