Hi,
16x^2 - 25y^2=400
Note:Standard Form of an Equation of an Hyperbola isopening right or left
where Pt(h,k) is a center with vertices 'a' units right and left of center. V are (±5,0)
Asymptotes passing thru the center with slope = ± b/a , y = ±4/5x
foci being ± sqrt(a^2 + b^2) from center along axis of symmetry y = b
foci are (±,0)