When asked to factor the trinomial #9x^2+12x+4#, a student gives the answer #(3x-2)(3x-2)#. Why is this wrong?
1 Answer
May 3, 2017
Explanation:
#"if we expand using Foil"#
#(3x-2)(3x-2)#
#=9x^2-6x-6x+4#
#=9x^2-12x+4#
#"when it should be " 9x^2color(red)(+12x)+4#
#rArr(3x+2)(3x+2)larrcolor(red)" are required factors"#
