Find an equation in standard form for the hyperbola with vertices at (0, ±4) and asymptotes at y = ±1/3.x.
a. y squared over 144 minus x squared over 16 = 1
b. y squared over 16 minus x squared over 36 = 1
c. y squared over 16 minus x squared over 144 = 1
d. y squared over 36 minus x squared over 4 = 1