This is the second version of a task asking students to find the areas of triangles that have the same base and height. This presentation is more abstract as students are not using physical models. They still determine the area of each...

Learn a formula, created thousands of years ago, that you can use to calculate the area of a triangle if you know all three sides' lengths.

[Free Registration/Login may be required to access all resource tools.] Find the area of a triangle when all three sides are known.

In this activity, students use the Geoboard to determine the area of triangles using the surrounding rectangle technique. They also develop and use formulas to determine the area of triangles. [Requires Adobe Reader.]

[Free Registration/Login may be required to access all resource tools.] This lesson covers Heron's Formula and problem solving using trigonometry.

Students will measure the lengths of the sides of three different triangles and apply Heron's Formula to calculate the area in acres. The measurements for this activity may be done outside or, using a specified scale, completed inside....

Learn about corresponding angles with this resource which offers detailed explanations, examples, and interactives. Subjests covered include the area of a triangle. Links to related topics.

Learn about the area of an equilateral triangle with this helpful reference tool. Provides a detailed definition, examples, and an internet activity that enhances further explanation. Includes links to related topics.

This tutorial provides a brief introduction about what area is, then gives the formulas for area of a square, rectangle, parallelogram, trapezoid, triangle, and circle. Examples of each formula are provided.

[Free Registration/Login may be required to access all resource tools.] An alternate formula for the area of a triangle.

Discusses how to find the area of a triangle using Heron's formula and provides interactive examples and problems you can solve.

Sixth graders find the area of a trapezoid by decomposing it into triangles and using the formula

Three circles are mutually tangent. Students are asked to find the total area of the circles plus the area inside where they meet. Students will need to know how to calculate the area of a circle, a sector of a circle, and an equilateral...

Define's Heron's Formula and provides examples for how to use the formula to calculate the area of a triangle.

This site provides the user with a useful reference to different geometric forms, their elements, formulas, and areas. Entirely in Spanish.

This activity allows students to find the area of a triangle using Heron's formula.

Students draw trapezoids and investigate their properties. They derive the area formula for a triangle from the area formula for a trapezoid. They also investigate the terms: Isosceles trapezoid and Tessellation. Numerous supplementary...

This MathWorld site offers a lesson on finding the midpoint of a line segment using a compass and finding the midpoint of the sides of a triangle. This site also has an interesting way of drawing two triangle with equal area by finding...

Seventh graders find the area of regular polygons, recalling what they already know about the area of geometric shapes and generalizing a formula for any regular polygon.

Introduces how to set up and solve simple geometric-figure word problems. Includes advice regarding formulas to memorize.