standard_description: Derive the formula A = 1/2 ab sin(C) for the area of a triangle by drawing an auxiliary line from a vertex perpendicular to the opposite side.
problem_activity: Stage 1: Lines of Symmetry
Required Preparation
Materials to Gather
Colored pencils, crayons, or markers
Materials to Copy
Blackline Masters
Centimeter Grid Paper - Standard
Centimeter Dot Paper - Standard

Narrative
Each student chooses whether to use dot or grid paper. Each student creates a half of a design and draws a line of symmetry. Students switch paper and complete each other’s designs.


aligns: no