Answer: c. 4.5
Step-by-step explanation:
If x varies directly with y, we can set up a proportionality equation:
x/y = k
where k is the constant of proportionality.
Given that x = 3.5 when y = 14, we can plug these values into the equation:
3.5 / 14 = k
k = 3.5 / 14
k = 0.25
Now that we have the constant of proportionality, we can use it to find x when y = 18:
x / 18 = 0.25
x = 0.25 * 18
x = 4.5
Therefore, when y = 18, x is equal to 4.5.
