Answer:
84
Step-by-step explanation:
The initial statement is y directly proportional to x square and inversely proportional to z
to convert an equation multiply by k the constant of variation
y=k*((x*x)/z)
K x square/z
to find k use the given condition
y=12 when x=2and z=7
y= k x square /z
yz/x square = k
12*7/4
84/4
21
equation is y = 21x square / z
when x=4 and z= 4
y= 21*16/4
84 is the answer
