how do you factor 3b^2-9b-30

Question

anonymous · Answer

Use the factor theorem so anything that 30 can be divisible by in the positive and negative. and that equals to zero.

anonymous · Answer

and then you can use synthetic or long division.

anonymous · Answer

Oh ok I see. Thank you!

radar · Answer

First remove the 3 which is common to all terms now you have
3(b^2-3b-10)
now it appears that the expression in the parenthesis can now be factored.

anonymous · Answer

That makes sense. But im not really sure how to factor from there

anonymous · Answer

http://www.wolframalpha.com/ Your best buddy

radar · Answer

3(b-5)(b+2).  Note that the product of -5 and +2 = -10 which is needed for the last term, further note the the sum of -5 and +2 is equal to -3 which is needed in the 2nd term.

anonymous · Answer

Haha, simpler your way.

radar · Answer

And as jiji501 posted that link can be very helpful.

anonymous · Answer

cool. i'll check it out!:D and thanks radar and jiji501