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: Area Formulas App
Students review the definition and area formula for the rectangle, square, parallelogram, triangle, trapezoid, and circle.
Cuemath
Cuemath: Area of a Circle
This mini-lesson explores the area of a circle. Provides a definition, examples, and practice questions with answers.
Free Math Help
Free Math Help: Area Formulas
The resource consists of area formulas and diagrams for a square, rectangle, circle, triangle, and trapezoid.
University of Waterloo (Canada)
University of Waterloo: Cemc: Math Circles: 3 D Geometry Ii [Pdf]
This worksheet provides a variety of 3D geometry questions requiring higher order thinking skills. Questions include; finding the surface area of a prism, surface area of pyramid, surface area of a sphere, and platonic solids.
Texas Instruments
Texas Instruments: Arc Length and Area of Sectors
This is an introduction to finding the arc length and area of sectors of circles. Students should have the formulas for Circumference and Area of circles.
George Mason University
Area Formula Lab
In this set of worksheet activities, students will be guided to discover formulas for area of polygonal shapes and circles.
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.
Texas Education Agency
Texas Gateway: Determining Area: Sectors of Circles
Students will use proportional reasoning to develop formulas to determine the area of sectors of circles. Students will then solve problems involving the area of sectors of circles.
Khan Academy
Khan Academy: Area of a Circle
Find the area of a circle given its radius, diameter, or circumference. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Cuemath
Cuemath: Circles
Explore everything about circles. Learn various parts of a circle like a diameter, radius, circumference, circles chord, tangent circles, major arc, segment, sector, and discover other interesting aspects of it. Try your hand at solving...
Texas Education Agency
Texas Gateway: Determining Area: Regular Polygons and Circles
The student will apply the formula for the area of regular polygons to solve problems.
Khan Academy
Khan Academy: Area and Parts of Circles
Practice finding the area or circumference of part of a circle. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.
Cool Math
Coolmath: Precalculus Basic Formulas to Know
This CoolMath resource provides an introduction to some Precalculus formulas.
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]
Oswego City School District
Regents Exam Prep Center: Area of Polygons and Circles
How would you find the area of a polygon or circle? Explore this concept with engaging activities at this test prep site. Here you will find detailed problem solving strategies with accompanying visuals, a reference table with formulas,...
Texas A&M University
Wtamu Virtual Math Lab: Beginning Algebra: Formulas
This tutorial will show you how using formulas can help you solve problems. Include formulas for various geometric shapes and steps showing how to use them.
Illustrative Mathematics
Illustrative Mathematics: G C Mutually Tangent Circles
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...
CK-12 Foundation
Ck 12: Geometry: Area of a Circle
[Free Registration/Login may be required to access all resource tools.] In this lesson students calculate the area of circles and the area of sectors of circles by using given information and formulas. Students examine guided notes,...
National Council of Teachers of Mathematics
The Math Forum: Elementary Geometry Circles
The Math Forum offers an archive of question and answer sessions on circles and how they relate to geometry.
OER Commons
Oer Commons: Area of a Circle
Seventh graders will compare the formula for the area of a regular polygon to discover the formula for the area of a circle.
Google
Google for Education: Area of a Circle
Students learn to derive the formula for the area of a circle. They learn to relate a circle to a parallelogram and rectangle while learning the concept of infinity as they imagine slicing an circle into infinitesimally small slices.
Wolfram Research
Wolfram Math World: Heron's Formula
This site provides a detailed overview of Heron's Formula. Content includes a definition, example, and formula.