Hi
Standard Form of an Equation of an Hyperbola opening right/left is
where Pt(h,k) is a center with vertices 'a' units right and left of center.
Asymptote is y = -x b/a = 1 or a = b
Foci at (-4,0) and (4,0) Pt(0,0) is the center
4 = sqrt(a^2 + a^2) = sqrt(2a^2) a = sqrt(8)= b
x^2/8 - y^2/8 = 1
