Seudónimo Seudónimo 19-11-2017 Mathematics contestada y and x have a proportional relationship, and y = 12 when x = 5. What is the value of y when x = 8? y and x have a proportional relationship, and y = 7 when x = 2. What is the value of x when y = 21? Which equation represents a proportional relationship? y=12x y=2(x+13) y=−3x+2 y = 3x