How do you solve #2x^2+11x+5=0#?

1 Answer
Jim G.
Apr 11, 2018

#x=-5" or "x=-1/2#

Explanation:

#"using the a-c method to factorise"#

#"consider the factors of the product "2xx5=10#
#"which sum to + 11"#

#"the required factors are + 10 and + 1"#

#"split the middle term using these factors"#

#2x^2+10x+x+5=0larrcolor(blue)"factor in groups"#

#rArrcolor(red)(2x)(x+5)color(red)(+1)(x+5)=0#

#"take out the common factor "(x+5)#

#rArr(x+5)(color(red)(2x+1))=0#

#"equate each factor to zero and solve for x"#

#x+5=0rArrx=-5#

#2x+1=0rArrx=-1/2#

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