point. This circle is not differentiable at (−5,0) and (5,0). (The d.e. shows
undefined when y = 0, and the slope field shows vertical tangents along the x-
axis.) Hence, the particular solution includes only the semicircle in quadrants
III and IV.
Solving x^2 + y^2 = 25 for y yields . The particular solution through
point (4, −3) is with domain −5 < x < 5.