Exercise 22 Page 384

For plane M and NB to intersect at point A, A has to lie in plane M. We will, therefore, start by sketching a plane M and point A in the plane.

We can now place points N and B somewhere on opposite sides of plane M and draw the ray NB passing through A, to get the desired sketch.

Note that there are infinitely many ways to sketch the figure. All of them are correct, as long as the ray starts at N, intersects the plane at A, and passes through B.