You can put this solution on YOUR website!
The way I did this was I set it up as long division and
I tried to guess what the divisor should be
(15*x^3-6*x^2-5*x*b+2*b) / something = something
I wanted the divisor and the 1st term of the result to come as
close as possible to cancelling out the 1st 2 terms,
15x^3 - 6x^2
3 and 5 worked for factors of 15
I put 5x in the divisor
that made the 1st term of the result 3x^2
what did I need to add to 5x to cancel out 16x^2, the 2nd term?
-2 did it
so my divisor is 5x-2
now what to add to 3x^2 to cancel -5xb + 2b?
-b does it
so my answer is (5x -2)*(3x^2 - b)
hope that's not unclear
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