How do you factor #3x^3 + 27x^2y – 24xy – 216y^2#?
1 Answer
Mar 28, 2016
#3x^3+27x^2y-24xy-216y^2=3(x^2-8y)(x+9y)#
Explanation:
Separate out common scalar factor
#3x^3+27x^2y-24xy-216y^2#
#=3(x^3+9x^2y-8xy-72y^2)#
#=3((x^3+9x^2y)-(8xy+72y^2))#
#=3(x^2(x+9y)-8y(x+9y))#
#=3(x^2-8y)(x+9y)#
