How do you factor #5x^3+15x^2-20x#?

Question

6635 views around the world

You can reuse this answer
Creative Commons License

Answer 1 · 2018-05-26T17:52:20

#5x(x+4)(x-1)#

#"take out a "color(blue)"common factor "5x#

#=5x(x^2+3x-4)#

#"the factors of - 4 which sum to + 3 are +4 and - 1"#

#=5x(x+4)(x-1)#

Answer 2 · 2018-05-26T17:56:09

#5x(x-1)(x+4)#

We get
#5x(x^2+3x-4)#
Solving
#x^2+3x-4=0#
we obtain
#x=1#
or
#x=-4#
so finally we get
#5x(x-1)(x+4)#

Answer 3 · 2018-05-26T17:56:22

#5x^3+15^2-20x=color(blue)(5x(x+4)(x-1)#

Factor:

#5x^3+15x^2-20x#

Factor out the GCF #5x#.

#5x(x^2+3x-4)#

Find two numbers that when added equal #3#, and when multiplied equal #-4#. The numbers #4# and #-1# meet the requirements.

#5x(x+4)(x-1)#