Need Help please!

a)  r  =      2

          __________       

            5 +  7cos θ

Standard Form  is

r  =     ep

      ___________

       1 + e cos θ

We  need   a "1" as a constant in the denominator to put this into SF.....divide every term by 5

r  =       2/5

       ____________

        1 + (7/5)cos θ

The eccentricity, e,  =   7/5

If

0 ≤ e < 1      we have an ellipse

e = 1     we have a parbola

1 < e  we have a hyperbola

So.....this is a hyperbola

(b)   If this is an ellipse....we must have that

0 ≤ e < 1

0 ≤ b / 5 < 1

0 ≤ b < 5