How do you factor the trinomial #4x^2+2x-20#?

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Answer 1 · 2015-11-26T03:21:44

#4x^2+2x-20=2(2x+5)(x-2)#

#4x^2+2x-20#

Factor out the GCF #2#.

#2(2x^2+x-10)#

Factor the remaining trinomial using the AC method, where #a=2, b=1, and c=-10#.

Multiply #a# times #c#.

#2xx-10=-20#

Find two numbers that when added equal #1# and when multiplied equal #-20#. The numbers #5# and #-4# meet the criteria.

Rewrite the trinomial substituting #5x# and #-4x# in place of #x#.

#2(2x^2+5x-4x-10)#

Separate the two pairs of terms.

#2(2x^2+5x)-(4x-10)#

Factor #x# out of the first pair of terms.

#2(x(2x+5)-(4x-10)#

Factor #-2# out of the second pair of terms.

#2(x(2x+5)-2(2x+5)#

Factor out #(2x+5)#.

#2(2x+5)(x-2)#