Interior angles in a triangle add up to 180˚. Triangles close triangleA polygon with three straight sides. have three sides, therefore they have three angles. Interior angles in a triangle sum to a ...

Trigonometry close trigonometryThe study of sides and angles in triangles. can be used to find a missing angle in a right-angled triangle when two sides are known. An understanding of the three ...

Depicted above are two similar triangles; their sides are parallel. The largest angle in either triangle above is 66 degrees. The smallest angle in either triangle above is 52 degrees. The inner ...