Finding Optimal Consumption Bundle Suppose u(x,y)=min{x+y,4(x)^1/2,4(y)^1/2} , Px=1, Py=2, M=5 . Here, Px, Py and M are the price of x, price of y, and the Income. 

Give an example of the optimal consumption bundle of x and y for this consumer.

I know to plot the Indifference Curve given a value of Utility,however how could I know what is the maximum utility that can be obtained in this case?
In this case the optimal choice is $(x^*, y^*) = (3, 1)$. Here is the picture :