[tex]\huge\text{Hey there!}[/tex]
[tex]\large\textsf{3(7x - 6)}\\\large\rightarrow\textsf{3(7x) + 3(-6)}\\\large\rightarrow\textsf{21x - 18}\\\\\\\huge\text{Therefore, your answer is: \boxed{\textsf{21x - 18}}}\huge\checkmark[/tex]
[tex]\large\textbf{Note: All you had to do is DISTRIBUTE 3 the}\\\large\textbf{WITHIN PARENTHESES. }\large\checkmark[/tex]
[tex]\huge\text{Good luck on your assignment \& enjoy your day!}[/tex]