The given image is a triangle.
Property of triangle:
A triangle has three sides.
A triangle has three angles.
A triangle has three vertices.
To find the sides, angles and vertices of the triangle RST:
Sides of the triangle SRT:
RS, ST and RT
Angles of the triangle RST:
∠A, ∠B and ∠C
Vertices of the triangle RST:
A, B and C
These are sides, angles and vertices of the triangle.