How do you solve #2x^2-116= - x ^ { 2} + 247#?
1 Answer
Dec 14, 2017
Explanation:
#"add "x^2" to both sides"#
#2x^2+x^2-116=cancel(-x^2)cancel(+x^2)+247#
#rArr3x^2-116=247#
#"add 116 to both sides"#
#3x^2cancel(-116)cancel(+116)=247+116#
#rArr3x^2=363#
#"divide both sides by 3"#
#(cancel(3) x^2)/cancel(3)=363/3#
#rArrx^2=121#
#color(blue)"take the square root of both sides"#
#sqrt(x^2)=+-sqrt121larrcolor(blue)"note plus or minus"#
#rArrx=+-11#