Question 738617
You have one square botton with side x, and three rectangle sides or "panels" with length x and height 3 inch.


Sum of the outside area of the open box: {{{x*x+4*x*3}}}

Description says that the outside area of this box is 493 inch^2, which means
{{{x^2+4x*3=493}}}, or {{{highlight(x^2+12x=493)}}}.
You take it from there to finish.