Among all pairs of numbers (x, y) such that 3x + y = 16, find the pair for which the sum of squares, x² + y², is minimum. Write your answers as fractions reduced to lowest terms.
"Among all pairs of numbers (x, y) such that 3x + y = 16, find the pair for which the sum of squares, x² + y², is minimum. Write your answers as fractions reduced to lowest terms."