I need the answer to #3

Radii ok and nl are perpendicular to om because of the radius-tangent theorem. by definition of perpendicular, angles kom and lnm are right angles. this means that triangles kom and lnm are right triangles. angle lmn is common to both right triangles, so by the triangles kom and lnm are similar.

Given the graphed function below which of the following orders pairs are found on the inverse function

What is always true when two whole numbers are subtracted?