Geometry
See classic geometry come alive. Drag points to test theorems, watch proofs rearrange themselves, and apply transformations to shapes on the coordinate plane.
Key concepts
Euclidean Geometry
Points, lines, angles and shapes, and the relationships that always hold between them
Proofs
Show why a statement is true for every case, often by rearranging areas or using congruence
Transformations
Translations, rotations, reflections and dilations that move or resize figures
Coordinate Geometry
Describe shapes with coordinates so geometry can be done with algebra
Visualizations
Pythagorean Theorem
BeginnerWatch a² + b² = c² proved visually with squares on the sides of a right triangle
Right TrianglesVisual ProofDistance Formula
Open Geometric Transformations
BeginnerTranslate, rotate, reflect and dilate shapes on the coordinate plane
TranslationRotationReflectionDilation
Open Triangle Centers
IntermediateDrag the vertices of a triangle to explore its centroid, circumcenter, incenter and orthocenter
CentroidCircumcenterIncenterEuler Line
Open