For each equation, determine whether x and y are directly proportional (that is, if the equation shows direct variation).
If so, then find the constant of proportionality (the constant of variation).
(a) 5/4 x = y
O Proportional
Constant of proportionality: k =
O Not proportional
(b) y = -x
O Proportional
Constant of proportionality: k =
O Not proportional
