Khan Academy
Khan Academy: Use Pythagorean Theorem to Find Area and Perimeter
Find the area and perimeter of triangles and quadrilaterals by first using the Pythagorean Theorem to find missing side lengths. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video, or...
Cuemath
Cuemath: Triangles
Explore everything about triangles. Learn about the different types, important properties, and how to find its area and perimeter. Check out the solved examples and interactive questions for better understanding.
CK-12 Foundation
Ck 12: Geometry: Perimeter and Area Study Guide
[Free Registration/Login may be required to access all resource tools.] This study guide looks at the definitions and units for perimeter, area, and circumference, and at the perimeter and area of different shapes, including regular...
CK-12 Foundation
Ck 12: Geometry: Triangle Area Grades 6 7
[Free Registration/Login may be required to access all resource tools.] Find the areas of triangles given their base and height dimensions.
Khan Academy
Khan Academy: Area of Triangles
Demonstrates the logic behind the formula for the area of a triangle. Includes several practice problems and their explanations.
National Council of Teachers of Mathematics
Nctm: Illuminations: Area of Triangles
To find the area of a triangle, try to make a parallelogram using a copy of the triangle.
University of Georgia
University of Georgia: Inter Math: Recommended Investigations of the Triangle
Investigate the qualities of a triangle with these seventeen word problems. Many include ways to extend the lesson.
Khan Academy
Khan Academy: Area & Perimeter on the Coordinate Plane
Find the area or perimeter of shapes like triangles, rectangles, parallelograms, and hexagons on the coordinate plane.
Khan Academy
Khan Academy: Area of Triangles
Practice finding the area of right, acute, and obtuse triangles. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Homeschool Math
Homeschool Math: Area of Triangles
This lesson presents the idea that the area of any triangle is exactly half of a certain parallelogram -- thus we get the familiar formula of multiplying the base and the altitude and taking half of that. The lesson contains varied...
Cuemath
Cuemath: Right Angled Triangle
Explore and learn about the features and properties of a right triangle in this lesson. Includes examples and practice questions.
Math Open Reference
Math Open Reference: Perimeter of a Triangle
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.
Shodor Education Foundation
Shodor Interactivate: Triangle Explorer
Students explore the nature of triangles and their area. An applet and instructor resources are included. [Requires Java.]
Math Open Reference
Math Open Reference: Triangles
A complete reference guide to types of triangles and triangle perimeter and area. It provides definitions and interactive animated activities that enhance further explanation.
Illustrative Mathematics
Illustrative Mathematics: G Gpe Triangle Perimeters
Students are shown two triangles touching points on a coordinate grid and are asked to answer questions about their perimeters. The purpose of this task is to apply the Pythagorean theorem to calculate distances and areas. Aligns with...
SMART Technologies
Smart: Area of a Triangle
This SMART whiteboard activity will help students learn the formula for finding the area of a triangle. Students will practice what they have learned by using examples created for visual and kinesthetic learners.
Khan Academy
Khan Academy: Areas of Shapes on Grids
In this exercise, students practice finding the areas of shapes on grids. Students receive immediate feedback and have the opportunity to get hints and try questions repeatedly.
CK-12 Foundation
Ck 12: Geometry: Area of Composite Shapes Involving Triangles
[Free Registration/Login may be required to access all resource tools.] In this lesson students find areas of combined figures involving triangles. Students examine guided notes, review guided practice, watch instructional videos and...
Math Slice
Math Slice: Area & Perimeter: Math Worksheets
This tool allows you to create worksheets of word problems at varying levels of difficulty where students must calculate the area or perimeter of different polygon shapes. You can choose to set up the page using any of these polygon...
ClassFlow
Class Flow: Area of Triangles
[Free Registration/Login Required] This flipchart explores the formula for finding the area of a triangle. Examples and hints are given to help students. A video clip is included, showing how to find the height of a triangle, given the...
Better Lesson
Better Lesson: Finding the Area Review and Assessment
Sixth graders find the area of rectangles, triangles, parallelograms, and trapezoids by using formulas or by composing into rectangles or triangles.
CK-12 Foundation
Ck 12: Geometry: Triangle Area Grade 7
[Free Registration/Login may be required to access all resource tools.] Find the area of different triangles given the base and the height.
Better Lesson
Better Lesson: Finding the Area of a Triangle
Sixth graders find the area of a triangle using square units and the area formula.
Khan Academy
Khan Academy: Find Base and Height on a Triangle
Identify the height of a triangle when given the base. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.