Step-by-step explanation:
sine is the vertical distance of the point on the circle's arc from the horizontal diameter, which is therefore the y-coordinate of the point, because the center of the circle is also the origin of the coordinate grid.
sin A = 9/41 = 0.219512195...
cosine is the horizontal distance of the point on the circle's arc from the center of the circle. because the center of the circle is also the origin of the coordinate grid, this is the x-coordinate of the point.
cos A = 40/41 = 0.975609756...
tangent is simply sine/cosine.
so, in our case
tan A = sin A / cos A = 9/41 / 40/41 = 9/40 = 0.225
