K–12 · intermediate
Geometry
Angles, area, and spatial reasoning with precise calculation.
Skills
19 skills in 7 sections — fundamentals first, then more specific topics. Practice each until Mastery Score 100.
A.Angles4 skills
- A.1 Complementary & Supplementary AnglesPractice →Find the missing angle in a complementary or supplementary pair.
- A.2 Triangle Angle SumPractice →Find a missing angle in a triangle.
- A.3 Triangle Angles in a DiagramPractice →Use a labeled triangle diagram to find a missing interior angle.
- A.4 Angles from a DiagramPractice →Read a marked angle between two rays in a figure.
B.Parallel lines & transversals1 skill
C.Area & circumference5 skills
- C.1 Rectangle AreaPractice →Compute area of a rectangle.
- C.2 Triangle AreaPractice →Find the area of a triangle from base and height.
- C.3 Parallelogram & Trapezoid AreaPractice →Find areas of parallelograms and trapezoids.
- C.4 Circle AreaPractice →Compute area given radius (coefficient of π).
- C.5 CircumferencePractice →Find a circle's circumference in terms of π.