GEO-11 · Geometry and Trigonometry

Right-triangle trigonometry

Circles and trigonometry · Stage 3

01 · Key idea

Sine is opposite side divided by hypotenuse.

Useful rulesin, cos, tan

Build on: GEO-07

02 · Worked example

In a right triangle, the side opposite θ is 3 and hypotenuse is 5. Find sin θ.

This teaching example is original and is not an official SAT question.

Reasoning

sin θ=opposite/hypotenuse=3/5.

Answer

3/5

03 · Next step

Practice questions remain in English, as on the SAT.

GEO-11 · Right-triangle trigonometry