An ellipse has a center at the origin, a vertex along the major axis at open paren 20 comma 0 close paren , and a focus at open paren 16 comma 0 close paren The equation of the ellipse is in the form. the fraction with numerator x squared and denominator A squared plus the fraction with numerator y squared and denominator b squared is equal to 1 What is the value of b in the equation?