Show y = x^4 -2 and y = kx^2 intersect all k values, how?

if I use the discriminant what is the x^4 equal to like x^2 makes the a value one, what's x^4

Try completing the square?

Huh? Sorry, I don't understand what you're saying?

I was going to suggest, let $A = x^2$. You now have

$A^2 - kA - 2 = 0$

You know how to solve this.

If you like, let u=x^2 and consider the quadratic u^2-ku-2=0.

hi, thanks for answering, where has the u - k^2 come from?

I meant like usually when you substitute values into the discriminant from the equation, you know how you get an A value, a B value & a C value then use those values in b^2 - 4ac, I don't get what I'd use for that A value. I'd get stuck at k^2 - (4 x (a term) x -2) > 0, I don't understand what that term would be