Suppose that y varies jointly with w and x and inversely with z and when w = 15, x = 20, and z = 5, y = 420. Write the equation that models the relationship.(1 point) A y=7kwz y is equal to the fraction with numerator 7 k w and denominator z y=7wxz y is equal to the fraction with numerator 7 w x and denominator z
y=6kwz
y is equal to the fraction with numerator 6 k w and denominator
z
The equation that models the relationship is y = kwx/z, where k is the constant of proportionality.