Image of a figure (reflection in the x-axis) Animation Play

Images of figures Animation Play

Images under symmetry Animation Play

Inscribed angle in a semicircle Student activity Play

Inscribed circles, circumscribed polygons Student activity Play

Interesting information Animation Play

Interesting problems Student activity Play

Is a practical demonstration reliable? Whiteboard exercise Play

Is a practical demonstration reliable? Student activity Play

Isosceles triangles and symmetry Student activity Play

Kinds of triangles – classification by angles Student activity Play

Kinds of triangles – classification by angles Simulation Play

Kinds of triangles – classification by angles and sides Simulation Play

Kinds of triangles – classification by sides Simulation Play

Kinds of triangles – classification by sides Student activity Play

Lena's way Animation Play

Making a triangle Animation Play

Making angles that are multiples of 60° Student activity Play

Match a triangle Student activity Play

Match a triangle Whiteboard exercise Play

Miscellaneous problems Student activity Play

Mixed problems Student activity Play

More constructions Student activity Play

Mutual position of lines and interior angles in a triangle Whiteboard presentation Play

Mutual position of lines and interior angles in a triangle Class activity Play