The length of the perimeter is the sum of the lengths of the 4 sides. The length of the segment between (a, b) and (c, d) is given by the Pythagorean theorem as
length = √((c-a)² +(d-b)²)
The differences between adjacent points are
(3, 0) -(0, 0) = (3, 0) . . . . length 3
(3, 4) -(3, 0) = (0, 4) . . . . length 4
(6, 4) -(3, 4) = (3, 0) . . . . length 3
(0, 0) -(6, 4) = (-6, -4) . . . . length √(36+16) = 2√13
The perimeter is 3+4+3+2√13 = 10+2√13 ≈ 17.21
