How do you factor #3n ^ { 2} - 30n + 75# the trinomial completely?
1 Answer
May 16, 2018
Explanation:
#"take out a "color(blue)"common factor "3#
#=3(n^2-10n+25)#
#(a+-b)^2=a^2+-2ab+b^2" is a "color(blue)"perfect square"#
#"consider "n^2-10n+25#
#"with "a=n" and "b=-5#
#2ab=2xxnxx-5=-10n#
#rArrn^2-10n+25=(n-5)^2#
#rArr3n^2-30n+75=3(n-5)^2#
