Question

Factor 2x^3y-18x^2y-90y

Answer 1

The answer is:  " 2y (x³ − 9x² − 45)  " .
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Given:  2x³y − 18x²y − 90y  ;
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         We can factor out a   "2y"  ;   by looking out the "90y" as the term with the least number of variables.  We see that the terms has one "y" only;  and that ALL the all terms in the this expression have ONE "y" ; so we can factor out a "y".
              Then, we see that "2" is the smallest term (coefficient, in this case), in the expression, that that in the term:  "90y" ;  "90" is divisible by "2" ; as are all the other coefficient(s) in the expression (in this case, the one remaining, which is "18".  So, we can factor out a "2y" ; as follows:
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     →   2y (x³ − 9x² − 45) ;
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          Neither this expression — nor the expression in parentheses — can be factored any further;  so, this is our answer.
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