Answer:
B. W=kxy
Step-by-step explanation:
It stated that w varies jointly as x and y, so it means
W is equal to the constant of variation (k) multiplied to x and y.
For additional help, if you want to find its constant of variation (k) you have to divide w by x and y (if values are stated, needs the product of x and y). Like this:
[tex]k = \frac{w}{xy} [/tex]
