If you take b = 0 there is no triangle.
b = -2in makes no sense.
b = 0.5 in, 2 in and 7.9 in makes sense But if b = 7.9 in there exist some problem.
Calculating the height h, you must to divide the side b, and draw the corresponding segment.
You have two internal triangles, you obtain h by the Pitagora's theorem.
[tex]h^2 = 3.9^2 - (3.95)^2 < 0[/tex] Clearly makes no sense.
Note 3.9 is the value of the side a solving the relation in the text.
So, the possible values are 0.5 in and 2 in
