Triangle Solving Practice

Practice solving triangles.

You only need to know:

Try to solve each triangle yourself first, using pen and paper.

Then use the buttons to solve it step-by-step (more Instructions below).

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  • Look at the triangle and decide whether you need to find another angle using 180°, or use the sine rule, or use the cosine rule.  Click your choice.
  • The formula you chose appears, now click on the variable you want to find.
  • The calculation is done for you.
  • Click again for other rules until you have solved the triangle.

Note: answers are rounded to 1 decimal place.

What Does "AAS", "ASA" etc Mean?

It means which sides or angles we already know:

AAA Triangle AAS Triangle ASA Triangle SAS Triangle SSA Triangle SSS Triangle
Three Angles Two Angles and a Side not between Two Angles and a Side between Two Sides and an Angle between Two Sides and an Angle not between Three Sides