How do you factor #20b-15b^3#?

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Answer 1 · 2017-03-30T00:50:34

See the entire solution process below:

First, rewrite the expression as:

#(5b xx 4) - (5b xx 3b^2)#

Next, factor out the #5b#:

#5b(4 - 3b^2)#

Then, we can use this rule to factor the term in parenthesis:

#a^2 - b^2 = (a - b)(a + b)#

If we let #a^2 = 4# and #a = 2#. We can also let #b^2 = 3b^2# and #b = sqrt(3)b#

Substituting we can factor the term as:

#5b(2 - sqrt(3)b)(2 + sqrt(3)b)#