Question

Which of the following equations describes a hyperbola? (there may be more than one answer)
a) 16x^(2)+9y^(2)-64x+18y-71=0
b) 9x^(2)+16y^(2)+18x-64y-77=0
c) 9x^(2)-25y^(2)+54x-144=0
d) x^(2)-16y^(2)-2x+64y-79=0
e) 4y^(2)-25x^(2)+32y-36=0

Answer 1

c,d,e

Answer 2

how do you know that so fast?

Answer 3

the coefficients of x^2 and y^2 must have opposite signs

Answer 4

oh that was going to be my guess. thank you.