can someone show me how to factor:
-x^4+10x^2-9

Question

anonymous · Answer

$$x^2(-x^2+10)-9$$

anonymous · Answer

can you show me the steps? If i wanted the answer I could just use wolfram alfa.

anonymous · Answer

sorry, i just solved this, and the answer came right to me.

anonymous · Answer

Thanks for telling me about wolfram alfa. lol

anonymous · Answer

also, I want to know the factor by grouping method, which I think comes out a little differently.

anonymous · Answer

oh! You know what, my comp is super slow for some reason, I just got your messages.

anonymous · Answer

okay

anonymous · Answer

but really, can you help with factor by grouping? I keep forgetting...

anonymous · Answer

sorry.  i havent done factoring in months.

anonymous · Answer

yeah, me neither. Im finding real zeroes in this hmwk assignment and factoring is going a little silly in my head, lol

anonymous · Answer

Agrreed

anonymous · Answer

take x^2 as y,
-y^2+10y-9=0
multiply the whole thing with -1
y^2-10y+9=0
(y-1)(y-9)=0
the put back x^2 in place of y
(x^2-1)(x^2-9)=0
(x+1)(x-1)(x-3)(x+3)=0
I think this is the way, I haven't done this for about 9 years