A triangle has side lengths of left parenthesis, 1, point, 8, u, minus, 1, point, 3, v, right parenthesis(1.8u−1.3v) centimeters, left parenthesis, 3, point, 1, u, minus, 8, point, 6, w, right parenthesis(3.1u−8.6w) centimeters, and left parenthesis, 7, point, 6, w, minus, 3, point, 2, v, right parenthesis(7.6w−3.2v) centimeters. Which expression represents the perimeter, in centimeters, of the triangle?