Find the perimeter of a triangle

The perimeter is the length of all sides of the polygon. The perimeter is denoted by a capital Latin letter P. There are several ways to find the perimeter of a triangle, which one to use depends on the initially known data.

Find the perimeter knowing three sides

Side length A
Side length B
Side length C

Find the perimeter of a triangle, knowing its area and the radius of the inscribed circle

Area of a triangle S
Inscribed circle radius r

Find the perimeter of a triangle, knowing the two sides and the angle between them

Famous side А
Famous side B
Angle between sides α