Math Open Reference
Math Open Reference: Volume of a Triangular Prism
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.
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.
That Quiz
That Quiz: Practice Test: Triangles
Test your knowledge on the attributes of triangles. There are eleven levels that may be completed with or without a timer.
University of Cambridge
University of Cambridge: Nrich: Adding Triangles
Sharpen your logic and geometry skills by finding the area of a triangle. Solution available.
University of Cambridge
University of Cambridge: Nrich: Disappearing Square
This one page website explains how to find the area of a triangle with an interactive graphic. It then offers a challenge. The solution is available right at the website.
Varsity Tutors
Varsity Tutors: Hotmath: Review: Area
Find a quick, concise explanation of area and the formulas for different shapes. An example is given to help you understand how find the area of a shape. The area formulas are listed for different types of shapes.
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.
Math Planet
Math Planet: Pre Algebra: Measure Areas
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]
Shodor Education Foundation
Shodor Interactivate: Triangle Explorer
This applet allows users to study the nature of triangles and their area. It draws random triangles on a Cartesian coordinate system. The user can determine the area of the triangle using his or her preferred method. After the calculated...
University of Illinois
University of Illinois: Calculation of Triangle Area
Discusses how to find the area of a triangle using Heron's formula and provides interactive examples and problems you can solve.
Math Is Fun
Math Is Fun: Area of Triangles Without Right Angles
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.
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.
CK-12 Foundation
Ck 12: Geometry: Unknown Dimensions of Triangles Grade 6
[Free Registration/Login may be required to access all resource tools.] Find the unknown dimensions of a triangle given its area and another dimension.
Varsity Tutors
Varsity Tutors: Hotmath: Practice Problems: Areas of Triangles
Thirteen problems offer practice finding the areas of triangles. They are given with each step to the solution cleverly revealed one at a time. You can work each step of the problem then click the "View Solution" button to check each...
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...
Illustrative Mathematics
Illustrative Mathematics: 6.g Polygons in the Coordinate Plane
The purpose of this task is for students to practice plotting points in the coordinate plane and finding the areas of polygons. This task assumes that students already understand how to find areas of polygons by decomposing them into...
Purple Math
Purplemath: Determinant Word Problems
Matrix determinants can be used to solve many algebra and geometry word problems. Among them: finding the area of a triangle, finding the area of a parallelogram, and finding the equation of a line between two points. These three...
Illustrative Mathematics
Illustrative Mathematics: G Srt Extensions, Bisections, Dissections in Rectangle
For this task, learners must draw a diagram from a verbal description and use their understanding of similar triangles to find the area of a quadrilateral. Aligns with G-SRT.B.5.
Houghton Mifflin Harcourt
Holt, Rinehart and Winston: Homework Help: Perimeter and Area of Triangles and Trapezoids
Get independent practice working with finding the perimeter and area of triangles and trapezoids. Each incorrect response gets a text box explanation and another try. Correct responses are confirmed.
Illustrative Mathematics
Illustrative Mathematics: 6.g Same Base and Height, Variation 2
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...
Khan Academy
Khan Academy: Shaded Areas
Find the areas of shaded regions which are combinations of squares, triangles, and circles. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Khan Academy
Khan Academy: Area and Perimeter on the Coordinate Plane
Find the area or perimeter of shapes like triangles, rectangles, parallelograms, and hexagons on the coordinate plane. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
CK-12 Foundation
Ck 12: Trigonometry: Heron's Formula
[Free Registration/Login may be required to access all resource tools.] Find the area of a triangle when all three sides are known.
Illustrative Mathematics
Illustrative Mathematics: G C, G Srt Neglecting the Curvature of the Earth
Jerry and Ashley are trying to find out if it is possible to see the lowest point in the USA from the highest point in the USA. It turns out that the highest point in the United States, the peak of Mount Whitney, is only 85 miles from...