45x^3-63x^2+20x-28

Question

45x^3-63x^2+20x-28

psymon · Answer

Factor I assume?

anonymous · Answer

yes factor by grouping

psymon · Answer

Ah, okay. Well that means you will break the 4 terms into 2 groups of 2. I would group them together in the order given, so (45x^3- 63x^2) + (20x-28)
From there, your goal is to factor out the largest number possible out of each group as well as the largest power of x possible in each group. Your end goal is to have what is left inside each group of parenthesis to be the same.

anonymous · Answer

okay so tell me if I have this part right..... the first one would be 9x^2(5x-7x)?

psymon · Answer

Except it would only be -7, not -7x.

anonymous · Answer

I forgot it was ^2 already sorry

psymon · Answer

No reason to be sorry, you did fine. So yes, you would be left with 5x -7. This means that, if done properly, the other group of parenthesis should become 5x-7 when you factor something out.

anonymous · Answer

so the end would be(9x^2+4)(5x-7)?

psymon · Answer

Yeah, pretty much xD

anonymous · Answer

thank you for your help! Im horrible at this

psymon · Answer

No worries. Glad I could help. You got it pretty fast :P

anonymous · Answer

Im sure I will have more questions! LOL