Start with the question you are trying to answer
These guides connect the number returned by a calculator to the geometry behind it. They are written from a technical-drawing perspective: name the dimensions, show how they relate, work through a representative example, then use the visual result as a reasonableness check.
How to Solve Any Triangle
Choose SSS, SAS, ASA, AAS or SSA, then apply the sine rule, cosine rule or right-triangle relationships.
Read the guide → CirclesCircle Geometry Explained Visually
See how radius, diameter, chord, arc, sector, segment and annulus describe connected parts of a circle.
Read the guide → DraftingHow Scale Drawings Work
Convert between real and drawing dimensions and understand why a proportional screen view is not automatically a printed scale.
Read the guide → MeasurementArea vs Perimeter vs Surface Area vs Volume
Choose the right quantity and units for fencing, flooring, painting, capacity and material estimates.
Read the guide → Practical checksPractical Geometry for Builders, Makers and Drafters
Use diagonals, right triangles, slopes, arcs, offsets, areas and volumes to check real work.
Read the guide → Tank geometryPart-Full Horizontal Tank Volume
Understand the circular-segment calculation that makes fill percentage nonlinear with liquid depth.
Read the guide →Calculate, draw, then interpret
The calculators answer an immediate geometry question. A guide explains the relationship and common mistakes. The Methodology & Accuracy page documents calculation precision, approximations and limitations, while About Draw to Scale explains the drafting experience behind the project.