Is it possible to factor #y=3x^3+4x^2-75x-100 #? If so, what are the factors?
1 Answer
Feb 28, 2016
#(3x+4)(x-5)(x+5)
Explanation:
group the function into 2 'pairs' as follows.
#[3x^3 + 4x^2 ] + [ -75x - 100 ]# now factor each pair ( common factor )
1st pair :
#x^2(3x+4) # 2nd pair : -25(3x+4)
There is a common factor of (3x+4) in each pair.
hence: (3x+4)(
#x^2-25)#
# "now " x^2 - 25 " is a difference of squares "# which factors as (x-5)(x+5)
#" hence factors are " (3x+4)(x-5)(x+5)#
