Since the triangles are similar, their corresponding sides are in proportion.
We can set up the following proportion:
48 / 20 = (x + 16) / 16
We can then solve for x by cross-multiplying and simplifying:
48 * 16 = 20 * (x + 16)
768 = 20x + 320
448 = 20x
x = 22.4
Therefore, the value of x is 22.4.