Ok, I have two questions first:

1. I'm asked to find a cartesian equation for the polar graph of this polar equation: r^2 = sin(2(theta))
The answer I got was
(x^2+y^2)^2/(2xy) = 2
Is this the correct way to express it?

2. I need to find the cartesian equation for this parametric equation:
x = sec(t) + tan(t)
y = sec(t) - tan(t)
I have tried using the identity tan^2x + 1 = sec^2x, but I feel like I'm moving in circles!

I'd appreciate it so much if someone could help me!!! Thanks =)

2. x + y = 2 sec t
x - y = 2 tan t
(1/4)(x+y)^2 = (1/4)(x-y)^2 + 1
This gets rid of the t terms. Rearrange and simplify.