How do you factor #b^ { 3} - 5b ^ { 2} - 24b #?

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Answer 1 · 2017-07-17T14:52:06

See a solution process below:

First, we can factor out a #b# from each of the terms in the expression:

#b^3 - 5b^2 - 24b => (b * b^2) - (b * 5b) - (b * 24) =>#

#b(b^2 - 5b - 24)#

Playing with factors of #24# (1, 2, 3, 4, 6, 8, 12, 24) which when subtracted equal #-5# gives:

#b(b - 8)(b + 3)#

Answer 2 · 2017-07-17T23:57:42

#b(b+ 3)(b - 8)#

#f(b) = b(b^2 - 5b - 24)#

Factor the trinomial in parentheses.

Find 2 numbers knowing the sum #(b = - 5)# and the product #(c = - 24)#. They are: 3 and #- 8#.

Factored form:
#f(b) = b(b + 3)(b - 8)#