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...
CK-12 Foundation
Ck 12: Unknown Dimensions of Parallelograms Grades 6 7
[Free Registration/Login may be required to access all resource tools.] Find the unknown dimensions of a parallelogram given its area and another measurement.
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.
National Council of Teachers of Mathematics
The Math Forum: Seventh Grade Math: Area and Perimeter
Learn how to enlarge drawings, figure out how much tile to buy to cover a specific floor, and learn about area and perimeter. These and other lesson plans are provided, including a fun interdisciplinary plan featuring dragons.
CPALMS
Cpalms: Building Graduation Caps
[Free Registration/Login Required] In this lesson, students build geometric models of graduation caps using stiff paper. The activity requires the application of skills in finding surface area, understanding similarity, knowing the...