x/y + 9 = n for y

[math_celebrity]

x/y + 9 = n for y

First, subtract 9 from each side to isolate the y term:
x/y + 9 - 9 = n - 9

Cancel the 9's on the left side, and we get:
x/y = n - 9

Cross multiply:
x = y(n - 9)

Divide each side by (n - 9):
x/(n - 9) = y(n - 9)/(n - 9)

Cancel the (n - 9) on the right side, and we get:
y = x/(n - 9)