AASTriangle

AASTriangle[α, β, a] returns a filled triangle with angles α and β and side length a, where a is adjacent to one angle only.

Example

Create a triangle with angles of 30° and 60° and a side of length 2:

Graphics[AASTriangle[30 Degree, 60 Degree, 2]]

Please visit the official Wolfram Language Reference for more details.