Question

What is the equation of the hyperbola with vertices at (-4,0) and (4,0) and foci at (-5,0) and (5,0)?

A. x^2/16-y^2/9=1
B. y^2/16-x^2/41=1
C. x^2/16-y^2/41=1
D. x^2/9-y^2/16=1

Answer 1

the verts are along the x so B is out

Answer 2

the vert length is 4; so 16 should be under the x part; rules out D

Answer 3

the foci is at 5 and that makes it a 3-4-5 triangle by memory so go with a 9 under y

Answer 4

best guess; id go A

Answer 5

http://www.wolframalpha.com/input/?i=x^2%2F16-y^2%2F9%3D1