Teach the Cast

Some of GeometryForge’s cast are still learning. When you teach them, YOU learn it best — catch what they get wrong, then quiz them.

Teach the connections

Show how the geometry ideas connect

You've helped them one at a time. The real understanding is how the ideas CONNECT — teach that next.

Sir Transverse (parallel-line transversals (proportional segments — the intercept theorem)) × Scout Scale (dilation & similarity)

Why does drawing a line PARALLEL to one side of a triangle create a smaller SIMILAR triangle?

Master Tangent (tangent-to-a-circle & the tangent-chord angle) × Lady Inscribed-Angle (inscribed-angle circle theorems)

A tangent-chord angle and an inscribed angle both sit on the same arc. How are their sizes related?

Compass Wraith (locus — a circle is the set of points equidistant from a center) × Captain Construction (compass-and-straightedge constructions)

Why does swinging a compass from two points and marking the crossings give the perpendicular bisector?

Capstone — design a circular garden with a triangular bed

You're designing a round garden with a triangular flower bed inside. Each part below needs ONE of the cast's ideas — bring in the right person for each.

Plot the three corners of the bed as exact points on the grid.

Who do you bring in?

Find how much soil the triangular bed needs — its area.

Who do you bring in?

Check the bed is a right triangle: do the two short sides satisfy a² + b² = c²?

Who do you bring in?

Draw the round garden border with compass and straightedge.

Who do you bring in?

Resize the whole design to fit a bigger yard, keeping the exact shape.

Who do you bring in?

Your concept map

Your GeometryForge concept map

Each idea is a person you teach. A filled circle is one you can teach; a solid line is a connection you've taught. Fill the map by teaching the cast + their connections.

parallel-line proportions are what make shapes similarboth angles are measured by the same arca construction is a locus of equidistant points parallel-line proportions S Sir Transverse dilation & similarity S Scout Scale tangents & tangent-chord angle M Master Tangent inscribed-angle theorems L Lady Inscribed-Angle locus (equidistant points) C Compass Wraith compass-and-straightedge constructions C Captain Construction