[Free Registration/Login may be required to access all resource tools.] This lesson covers how to find the area of a triangle using sine.

To find the area of a triangle, try to make a parallelogram using a copy of the triangle.

Use this interactive tool to find the volume of a triangular prism. Try different figures for the height and the dimensions of the triangular face to see how these affect the volume. An accompanying chart also presents five methods for...

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

A complete reference guide to finding the volume of a triangle prism. It provides definitions, examples, and an interactive activity that enhances further explanation. Includes links to related topics.

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.

Demonstrates how to calculate the area of two-dimensional shapes using formulas. Covers parallelogram, triangle, trapezoid, and circle. Includes a video modeling how to find the area of a circle and a triangle. [0:59]

This lesson presents the idea that the area of any right triangle is exactly half of a certain rectangle, and contains varied exercises for students.

Learn how to find the area of triangles without right angles. Find the formula to use depending on the information you know about the triangle: base and height, three sides, or two sides and an angle.

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.

Explore and learn about the features and properties of a right triangle in this lesson. Includes examples and practice questions.

Explore the triangle inequality theorem with this helpful reference tool. Provides a detailed definition and an interactive activity that enhances further explanation. Includes links to related topics.

Basic exercises are presented to help students understand the concept of the area of triangles and the angles of a triangle.

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.

Use this calculator to calculate properties of a regular polygon. Enter any 1 variable plus the number of sides or the polygon name. Calculates side length, inradius, circumradius, area, and perimeter.