Solve for x, given that the polygons are similar

In trapezoid klmn, kj=19.2 and jm=22.5. identify ln.

Which one ? is the answer and how to find this answer

The graph of a function f(x)=(x+2)(x-4). which describes all of the values for which the graph is negative and increasing? all real values of x where x< -2 all real values of x where -2