Respuesta :
Answer:
z = 5xy
Step-by-step explanation:
since z varies jointly with x and y then
z = kxy ← k is the constant of variation
to find k use the given condition z = - 75 when x = 3 and y = - 5
k = [tex]\frac{z}{xy}[/tex] = [tex]\frac{-75}{-15}[/tex] = 5 and
z = 5xy ← equation of variation
Answer: z=kxy, k=5, z=-10
Step-by-step explanation: hope that helps
