How can you tell they’ve got it: Trigonometry basics?

If they’ve got it, you’ll see things like: Identify which trigonometric ratio to use (SOH CAH TOA) based on the known and unknown sides; Calculate an unknown side using sin, cos, or tan and a known angle; Find an unknown angle using the inverse trigonometric function (e.g. tan⁻¹). Or just try it together: If your child knows a ladder is 5 metres long and leans against a wall at 70° to the ground, can they use trigonometry to work out how high up the wall it reaches?

Mathematics Geometry Ages 13–15

Trigonometry basics

Your child can use sin, cos and tan in right-angled triangles. Knowing a ladder's length and its angle, they find how high it reaches.

In curriculum terms

Use the trigonometric ratios sin, cos, and tan in right-angled triangles to find unknown sides and angles, including setting up the correct ratio for a given problem

Ages are typical, not deadlines — follow your child’s pace. How to help at home →

How to tell they’ve got it

Tick these off as you see them — no test required.

Identify which trigonometric ratio to use (SOH CAH TOA) based on the known and unknown sides
Calculate an unknown side using sin, cos, or tan and a known angle
Find an unknown angle using the inverse trigonometric function (e.g. tan⁻¹)

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Try this together

If your child knows a ladder is 5 metres long and leans against a wall at 70° to the ground, can they use trigonometry to work out how high up the wall it reaches?

Where this sits on the map

Stuck here? Check the skills it builds on first. Confident? Here’s what it unlocks.

Builds on

Simple formulaeages 12–14Using trig ratios to find unknowns requires formula rearrangement

Types of anglesages 13–14Trigonometry extends Pythagoras by introducing angle-side relationships

Trigonometry basicsthis skill · ages 13–15

Unlocks

Nothing on the map depends on this yet.

solid = must come firstdashed = helps

Curriculum alignment

Where this fits in the official school curriculum — our best automated guess, not yet checked by a person.

This skill sits beyond Year 6 in the Australian Curriculum, so no F–6 code is matched. It also sits beyond the NSW K–6 syllabuses. It also sits beyond Level 6 in the Victorian Curriculum.

Nearby on the map

Types of anglesages 13–14 Angles in trianglesages 12–14 Angles with parallel linesages 12–14 Circles: Circumference & Areaages 12–14

All Geometry skills →