[tex]Identify \ common \ factor : \\\\ 168= \ \boxed{2} \cdot 2 \cdot 2 \cdot \boxed{3} \cdot 7 \\\\78= \boxed{2} \cdot \boxed{3} \cdot 13 \\\\Multiply \ the \ common \ factor : \ 2 \cdot 3 =6 \\ \\ Answer: \ The \ GCF \ of \ 168 \ and \ 78 \ is \ 6[/tex]
