Geometry Spot
Start with a lesson, sketch ideas in GeoSketch, then jump to calculators or practice problems whenever you need them.
Lessons on triangles, angles, circles, vectors, trigonometry, conics, and 3D geometry.
A free-draw canvas for points, lines, circles, and polygons. Explore geometry visually.
Browse every topic below, or open the learn hub to follow a guided path.
Build an intuition for why triangles are rigid shapes, how to classify them by sides/angles, and how classic theorems such as the angle sum emerge.
Master lines, rays, segments, parallelism, perpendicularity, and the full catalog of angles you will use across all geometry topics.
Compare rectangles, squares, parallelograms, and trapezoids with side-angle relationships, diagonals, and composite area reasoning.
Learn reliable methods for composite (irregular) figures: break shapes into rectangles/triangles, track the outer boundary for perimeter, and subtract cut-outs cleanly.
Understand radii, chords, tangents, circumference and area computations, and how arcs and sectors link measure with motion.
Blend algebra and geometry by representing vectors with coordinates, mastering operations, and interpreting dot products in context.
Move beyond classification to full triangle solving with sine/cosine laws, area techniques, and ambiguous-case reasoning.
Interpret sine, cosine, and tangent graphs, reduction formulas, and identity manipulations that power advanced geometry.
A modern 3D-geometry foundation: prisms, pyramids, cylinders, cones, spheres, plus surface area and volume formulas with interactive calculators.
Master the ellipse: standard equation, focal properties, eccentricity, and line–ellipse intersections with exam-style techniques and interactive visuals.
Learn hyperbolas deeply: standard forms, asymptotes, eccentricity (e>1), focal radius formulas, and intersection toolkits with real practice.
Build a complete parabola toolkit: focus–directrix definition, standard forms, latus rectum, focal chords, and line–parabola strategies.
Solve core 3D relationships: parallelism, perpendicularity, line–plane angles, dihedral angles, point-to-plane distance, and vector-method setups.
Geometry Spot brings lessons, tools, and practice together so you never have to jump between sites.
Structured lessons with visuals that break down geometry from the ground up.
Instant results for area, perimeter, angles, and more — no guesswork.
Curated sets with full solutions to help you check your understanding.
Every lesson, calculator, and formula sheet is completely free to use.
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Free lessons, calculators, and practice problems for every level — no sign-up needed.