Texas Education Agency
Texas Gateway: Area of Triangles, Parallelograms, and Trapezoids
These activities provide an opportunity for students to explore the area formulas for triangles, trapezoids, and parallelograms.
Math Planet
Math Planet: Geometry: Parallelogram, Triangles Etc
Resource examines the area of geometric solids through examples and a video lesson. [0:39]
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.
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]
Texas Instruments
Texas Instruments: Area Formulas App
Students review the definition and area formula for the rectangle, square, parallelogram, triangle, trapezoid, and circle.
National Council of Teachers of Mathematics
The Math Forum: Find the Area of the Shape!
Try to figure out the area of this challenging shape. In order to view the images, you will need to use JavaSketchpad.
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...
Mr. Martini's Classroom
Mr. Martini's Classroom: Area of Triangles, Trapezoids & Parallelograms
Students solve for the area of rectangles, squares, triangles, trapezoids, and parallelograms.
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...
Texas Education Agency
Texas Gateway: Determining Area of Composite Figures
Given composite figures (combinations of rectangles, squares, parallelograms, trapezoids, triangles, semicircles, and quarter circles), students will be able to determine expressions for the area as well as calculate the area of the figure.
Texas Education Agency
Texas Gateway: Determining Area: Composite Figures
Given information about composite fiugres, the student will determine the area of composite 2-dimensional figures comprised of a combination of triangles and parallelograms using appropriate units of measure.
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: Triangles and Quadrilaterals Study Guide
[Free Registration/Login may be required to access all resource tools.] This study guide reviews the formulas for area and perimeter of triangles and different kinds of quadrilaterals.
Texas Instruments
Texas Instruments: Getting Started With Area Formulas App
Calculate the Area of a Trapezoid This Concept Handheld Software Application reviews the definition and area formula for the rectangle, square, parallelogram, triangle, trapezoid, and circle.
Texas Instruments
Texas Instruments: Pearson Prentice Hall: Areas of Parallelograms and Triangles
Students will find the area of a parallelogram and the area of a triangle.
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.
Better Lesson
Better Lesson: Area of Composite Shapes
Sixth graders take their knowledge about area of rectangles, squares and triangles and apply it to parallelograms, trapezoids, and composite shapes.
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.
Oswego City School District
Regents Exam Prep Center: Area of a Triangle and Parallelogram Using Trig
How can trigonometry be used to find the area of a triangle or parallelogram? Does the triangle need to be a right triangle, and how accurate can the results possibly be? The answers to these questions are found here along with several...
The Math League
The Math League: Area and Perimeter
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.
BBC
Bbc: Area in General
You can pick up some valuable pointers on how to find the area of a triangle, rectangle, and other quadrilaterals. When you finish working your way through the pages you can take an on-line "Test Bite," and check your understanding.
Khan Academy
Khan Academy: Area Challenge
Practice solving problems involving triangles, parallelograms, and composite figures. Exercises include decimals, fractions, and word problems. Area of circles is not included. Students receive immediate feedback and have the opportunity...
Ministry of Education and Universities of the Region of Murcia (Spain)
Ministerio De Educacion Y Ciencia: Figuras Geometricas en El Plano
Interactive activities dealing with the areas of quadrilaterals figures.
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.