Trigonometry

Trigonometry is the math of angles and triangles — specifically, the relationships between angles and side lengths. It extends what you learned in geometry into a powerful toolkit used in construction, engineering, navigation, physics, and dozens of other fields.

Why Trigonometry Matters

Trig is everywhere in technical work:

• Carpenters use trig to calculate roof pitch, rafter lengths, and stair angles
• Electricians use trig for conduit bending angles and AC circuit analysis
• Surveyors use trig to measure distances and heights indirectly
• HVAC technicians use trig for ductwork angles and airflow calculations
• Machinists use trig for precision angle cuts and gear calculations

It’s also one of the most-tested subjects on the SAT, ACT, and GED math sections.

Where to Start

Start with SOH CAH TOA — the three basic trig ratios are the foundation everything else builds on. Then move to finding missing sides and angles, which is where trig becomes immediately practical. If you’re preparing for the SAT/ACT, prioritize SOH CAH TOA, special angles, and the unit circle.