Answer:
y = 65 when x = 13
Step-by-step explanation:
Here we have a proportion problem.
Y varies directly as x means that y equals the product of x and a constant
Let’s say our constant is k
Thus;
y = kx
now, k = y/x
Using the initial values;
k = 25/5 = 5
Now we want to get y when x = 13
Recall; y = kx
Thus using the value of k earlier calculated;
y = 13 * 5
y = 65
