Constructing Triangles

A triangle has three sides and three angles

To Construct a Triangle ...

... we need to know:

Three Angles Not Enough

• Two Angles and One Side, or
• One Angle and Two Sides, or
• Three Sides

When we only know three angles we don't know how large the triangle is.

Two Possible Solutions

When we know two sides and an angle not between them (Side-Side-Angle) there can be two possible triangles, or none at all!

How To Construct

There are many examples on the Constructions page.

Also see how to Construct A Triangle With 3 Known Sides.

And how to Construct An Equilateral Triangle.