the size s of the television screen recommended for a person who sits x feet from the screen ​(6
less than or equals
≤x
less than or equals
≤​15) is given by
Upper S left parenthesis x right parenthesis equals negative 0.227 x squared plus 8.155 x minus 8.8
S(x)=−0.227x2+8.155x−8.8 If a person buys a television set with a size s=42 inches screen, how far from the screen should the person sit