Can someone please help me with problem #6 of The Rational Root Theorem Worksheet?

I found the possible rational roots but I need the work shown for it. I also want you to show your work for how you got the factors of the constant and factors of the leading coefficient.

6. f(x) = 5x^4 + 32x^2 - 21

Below is an example problem for how you're supposed to do it:

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