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.
Khan Academy
Khan Academy: Area and Circumference of Circles Challenge
Try these challenge problems involving area and circumference.
CK-12 Foundation
Ck 12: Geometry: Unknown Dimensions Using Formulas Grade 7
[Free Registration/Login may be required to access all resource tools.] Given a perimeter or area of a figure, use formulas to solve for the unknown or missing dimensions.
CK-12 Foundation
Ck 12: Geometry: Surface Area of Cylinders
[Free Registration/Login may be required to access all resource tools.] Find the surface area of cylinders using formulas
CK-12 Foundation
Ck 12: Geometry: Surface Area of Prisms
[Free Registration/Login may be required to access all resource tools.] Use a formula and given information to calculate the surface area of different prisms.
Calculator Soup
Calculator Soup: Surface Area Calculator
Online calculator to calculate the surface area of geometric solids including a capsule, cone, frustum, cube, cylinder, hemisphere, pyramid, rectangular prism, sphere, spherical cap, and triangular prism
Mathigon
Mathigon: Geometry: Circle and Pi: Introduction
This lesson focuses on the characteristics of a circle including similarity, radius, circumference, and Pi. It provides formulas to determine the area of a circle, calculating Pi, and learning exercises throughout.
CK-12 Foundation
Ck 12: Geometry: Perimeter of Squares and Rectangles
[Free Registration/Login may be required to access all resource tools.] Find the perimeter of squares and rectangles.
Alabama Learning Exchange
Alex: Arc Lengths and Sector Areas
Students will work in cooperative groups to discover the relationships between arc length, central angle measure, and circumference. They will also discover the relationship between circle area, central angle measures, and sector area....
Alabama Learning Exchange
Alex: Surface Area of Pyramids and Cones
In this inquiry-based lesson, students will discover the formulas for the surface area of pyramids and cones. This lesson plan was created by exemplary Alabama Math Teachers through the AMSTI project.
Vernet -Virtual Education Resources Network
Salon Hogar: Referencia Rapida De Formulas Geometricas
This site provides the user with a useful reference to different geometric forms, their elements, formulas, and areas. Entirely in Spanish.
Purple Math
Purplemath: Geometry Word Problems: Introduction
Introduces how to set up and solve simple geometric-figure word problems. Includes advice regarding formulas to memorize.
ClassFlow
Class Flow: Area Rectangle
[Free Registration/Login Required] This flipchart will help students to solve the area for various rectangles on graph paper. It asks the students to define and solve for area using the appropriate formula.
ClassFlow
Class Flow: Area Rectangles
[Free Registration/Login Required] In this lesson students will understand area measured in square centimeters. They will understand and use the formula in words for the area of a rectangle.
Analyze Math
Analyze Math: Trapezoid Problems
The geometry tutorial examines the area, length, and vertices of a trapezoid. Topics include Heron's formula. The activity has several examples with detailed solutions.
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...
Khan Academy
Khan Academy: Solid Geometry Word Problems
In this exercise, students practice volume word problems with cones, cylinders, and spheres. Students receive immediate feedback and have the opportunity to watch a video, get hints, or try questions repeatedly.
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...
Cuemath
Cuemath: Cylinder
Mini-lesson takes a look at the definition and shape of a cylinder, cylinder formula, cylinder volume, and cylinder surface area. Try your hand at the cylinder surface area calculator and interactive questions for better understanding.
Wolfram Research
Wolfram Math World: World's Most Extensive Mathematics Resource
MathWorld provides a huge mathematics encyclopedia detailing the concepts of geometry, algebra, calculus, discrete math, number theory, and other math topics--complete with formulas, diagrams, examples, and references for thorough...
Oswego City School District
Regents Exam Prep Center: Cones
What is a cone? Find a definition, example images, and formulas for determining volume and surface area.
Oswego City School District
Regents Exam Prep Center: Prisms
What is a prism? Find a good definition and several example images, as well as formulas for finding the volume and surface area of a prism given measurements of its base and height.
Oswego City School District
Regents Exam Prep Center: Cylinders
What is a cylinder? Find a definition, example images, and formulas for determining the volume and surface area of a cylinder if given the radius of the base and the height.
Oswego City School District
Regents Exam Prep Center: Spheres
What is a sphere? Find a definition, example images, and formulas to help you determine volume and surface area given the radius.