Suppose f(x) = x^2+2. find the graph of f(2/3x)

Because the function is in the formula x^2 + 2, it will be symmetrical across the y axis.

This only leaves graphs 1 and 4.

I can't see the y values for your graphs; however, below are you plotting points - (X,Y)

(-5,18.66...), (-4,12.66...), (-3,8), (-2,4.66...), (-1,2.66...), (0,2), (1,2.66..), (2,4.66...), (3,8), (4,12.66...), (5,18.66...)