The perimeter P of a triangle is given by the formula P = a + b + c
\Where a, b and c are the side lengths of the triangle.
\The perimeter P of the triangle is
\P = 3.2 cm + 3.2 cm + 1.8 cm (Substitute a = b = 3.2 cm and c = 1.8 cm)
\= 6.4 cm + 1.8 cm (Add: 3.2 + 3.2 =6.4)
\ = 8.2 cm (Add: 6.4 + 1.8 =8.2)
The perimeter of the triangle is 8.2 cm.