The variables x and y vary inversely with a constant of variation of 7. Use the inverse variation formula, k = xy, to

find y when x = 9.

Given k = xy for inverse variation, we can find the constant of variation k by substituting the given values of x and y:

k = 7 (since x and y vary inversely with a constant of variation of 7)
x = 9

Now, we can solve for y using the formula k = xy:

k = xy
7 = 9y
y = 7/9
y = 0.7778

Therefore, when x = 9, y ≈ 0.7778 in the inverse variation relationship.