Geometry A complete geometry course, taught from the very beginning — no prior geometry assumed. One continuous track: every unit names what it builds on, every term is defined before it's used, and every idea comes with a figure you can touch.
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The course — 13 units, in order
01 Foundations: Points, Lines & Angles Points, lines, rays, segments and planes; measuring segments and angles; angle types, angle pairs, and bisectors. Start 02 Reasoning & Proof From noticing patterns to proving facts: conjectures, if-then statements, and your first two-column proofs. Start 03 Parallel & Perpendicular Lines Transversals and the angle pairs they create — which are congruent, which are supplementary — and proving lines parallel. Start 04 Triangles & Congruence Triangle types, the angle sum, the triangle inequality, and the congruence shortcuts SSS · SAS · ASA · AAS · HL. Start 05 Relationships in Triangles Bisectors, medians, altitudes, the midsegment theorem, and inequalities inside a triangle. Start 06 Quadrilaterals & Polygons Angle sums for any polygon; parallelograms, rectangles, rhombi, squares, trapezoids, and kites — with proofs. Start 07 Similarity Ratio and proportion, similar polygons, the AA · SSS · SAS similarity shortcuts, and the side-splitter theorem. Start 08 Right Triangles & Trigonometry The Pythagorean theorem, special right triangles, and sine · cosine · tangent with elevation and depression. Start 09 Circles Radius, chord, tangent, secant; central and inscribed angles; arcs; and the circle relationships. Start 10 Area & Perimeter Areas of triangles, quadrilaterals and regular polygons; circumference, circle area, sectors, and composite figures. Start 11 Surface Area & Volume Prisms, cylinders, pyramids, cones, and spheres — wrapping and filling 3-D solids. Start 12 Transformations Translations, reflections, rotations, and dilations; symmetry; congruence and similarity re-seen through motion. Start 13 Coordinate Geometry Distance, midpoint, and slope; equations of lines and circles; proofs with coordinates — the course capstone. Start