Question 335931
Hint: 


"You know that when a friend purchased four hamburgers, two fries, and three soft drinks, he paid $14" means that {{{4h+2f+3s=14}}} (where 'h' is the price per hamburger, 'f' is the price per fry, and 's' is the price per soft drink)



In addition, since "another friend purchased six hamburgers and six soft drinks for $18" we know that {{{6h+6s=18}}}



And finally, because "a third friend purchased five hamburgers, six fries, and eight soft drinks for $27", we can say that {{{5h+6f+8s=27}}}