The figure above represent the graph of

We are to approximate the value of y from the equation:

Taking log to the base 2 of both sides, we get:

In order to find the value of y, we first need to find the value of

from the graph. From the graph we can see that the value of log_{2}(3) is about 1.6, as shown in image attached with.
So,
y = 1.6/2 = 0.8
Thus value of y, as calculated using the graph is 0.8