Sophia Learning
Sophia: Sector Area of a Circle: Lesson 4
This lesson will demonstrate how to find the area and radius of a circle when given the sector area and central angle measure. It is 4 of 8 in the series titled "Sector Area of a Circle."
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.
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.
Science and Mathematics Initiative for Learning Enhancement (SMILE)
Smile: The Area of a Circle
An investigative approach is given to exploring finding the area of a circle.
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Pi and the Area of Circles
Contains a question pertaining to finding the area of a circle.
Other
Nearpod: Circles: Area and Circumference
In this lesson on circles, 7th graders will learn how to find the area and circumference of circles, semicircles, and compound shapes using formulas.
Other
Nearpod: Circles & Pi
In this lesson, 7th graders will learn vocabulary associated with circles and use formulas to find the area and circumference of circles.
CK-12 Foundation
Ck 12: Geometry: Radius or Diameter of a Circle Given Area
[Free Registration/Login may be required to access all resource tools.] Find the radius or diameter of a circle given the area of the circle
Science Struck
Science Struck: Cross Sectional Area of a Cylinder
Presents the formula and an example showing how to find the cross-sectional area of a cylinder. In this case, it is the same as the surface area for the circular faces.
Sophia Learning
Sophia: Determining Unknown Values Using the Volume of a Cylinder
This video lesson demonstrates how to work backward and use the volume of a cylinder to find an unknown value such as the radius or height. Students can check their understanding with an assessment. [4:41]
Common Core Sheets
Common Core Sheets: Geometry 7.g.4 Worksheets: Area and Circumference Circle
Worksheets provide practice with finding the area or circumference of a circle and answer keys are provided. You can even create your own worksheet or flashcards.
Khan Academy
Khan Academy: Circumference of a Circle
Find the circumference of a circle when given either the radius or diameter.Find the radius or diameter of a circle when given the circumference.Students receive immediate feedback and have the opportunity to try questions repeatedly,...
Khan Academy
Khan Academy: Circumference of a Circle
Practice finding the circumference of a circle.
Oswego City School District
Regents Exam Prep Center: Circles, Segments, and Area
A wealth of resources to supplement instruction on parts of the circle. Find lessons describing chords, tangents, secants, and segments, as well as related practice quizzes and classroom activities.
Texas Education Agency
Texas Gateway: Applying Geometric Probability
The student will find the area of polygons and circles. Then, the student will use probablity to solve real-world problems.
Cut the Knot
Cut the Knot!: Polygons: Formality and Intuition
This is a very interesting site about polygons. The site begins by distinguishing between shapes whose sides intersect and polygons whose sides do not overlap. After this short introduction, you will find information regarding area and...
Analyze Math
Analyze Math: Polygons Problems
Here are four problems about the area of a regular polygon. Start by finding the area of a hexagon inscribed in a circle of radius 10, and end by proving that as the number of sides of the polygon increases, the area of the polygon...
CK-12 Foundation
Ck 12: Geometry: Radius or Diameter of a Circle Given Area
[Free Registration/Login may be required to access all resource tools.] Find the radius or diameter of a circle given its area.
Curated OER
Visual Calculus: Area of a Circle
Students will be able to use The Method of Exhaustion and find the area of a circle by illustrating graphically.
Calculator Soup
Calculator Soup: Circle Calculator
Use this circle calculator to find the area, circumference, radius, or diameter of a circle. Given any one variable A, C, r or d of a circle you can calculate the other three unknowns.
Houghton Mifflin Harcourt
Holt, Rinehart and Winston: Homework Help Independent Practice: Circles
Get independent practice working with finding the circumference, area and radius of circles. Each incorrect response gets a text box explanation and another try. Correct responses are confirmed.
Illustrative Mathematics
Illustrative Mathematics: G C, G Srt Setting Up Sprinklers
In this task, students must decide where to place sprinklers on a lawn so that the maximum area of the lawn will be watered. To solve it, they must find areas of sectors of circles and use trigonometric ratios to solve right triangles....
Math Words
Math Words: Right Circular Cylinder
Find a picture of a right circular cylinder here with the formulas for volume, total surface area, and lateral surface area. Site by MathWords.com.
Texas Instruments
Texas Instruments: Numb3 Rs: Meltdown
Based off of the hit television show NUMB3RS, this lesson has students explore the relationship between a circle's area and it's radius. This is framed in the context of a scene in where a pile of ice is melting into an increasingly...