What is the constant of proportionality in the equation 6y=3x6y=3x6, y, equals, 3, x?

For this case we have the following equation:
 6y = 3x
 From here, we must clear the value of y.
 We have then:
 y = (3/6) x
 Rewriting we have:
 y = (1/2) x
 The proportionality constant is:
 k = 1/2
 
 the constant of proportionality in the equation 6y = 3x is:
 1/2