Answer:
y = 9
Step-by-step explanation:
If x and y are directly proportional, then the quotient y : x is constant.
We have:
x = 6 and y = 3
x = 18 and y = ?
We have the equation:
[tex]3:6=y:18\\\\\dfrac{3}{6}=\dfrac{y}{18}\qquad\text{cross multiply}\\\\6y=(3)(18)\\\\6y=54\qquad\text{divide both sides by 6}\\\\\dfrac{6\!\!\!\!\diagup y}{6\!\!\!\!\diagup}=\dfrac{54}{6}\\\\y=9[/tex]
