Zhi bought 18 tickets for games at a fair. Each game requires 3 tickets. Zhi wrote the
 expression 18-3g to find the number of tickets she has left after playing g games.
 Diego correctly wrote another expression, 3(6- g), that will also find the number of
 tickets Zhi has left after playing g games.
 Use the drop-down menus to explain what each part of Zhi's and Diego's expressions
 mean.