In order to determine the value of y, consider that a proportional relationship in between two variables can be writtes as follow:
y = kx
where k is the constant of proportionality, x is the time in minutes and y is the water elevel in centimeters.
To determine the value of k, calculate the quotient in between 14 and 5:
k = 14/5 = 2.8
Then, the equation is:
y = 2.8x
when x = 10, you obtain for y:
y = 2.8(10)
y = 28
Hence, the value of y is 28
