\[\boxed{\text{225\ (225).\ }\text{Еуроки\ -\ ДЗ\ без\ мороки}}\]
\[f(x) = 3x - 7\]
\[1)\ при\ x = - 3:\ \ \]
\[f(x) = 3 \cdot ( - 3) - 7\ \]
\[f(x) = - 16.\ \]
\[2)\ при\ x = 2\frac{1}{3}:\ \]
\[\text{\ f}(x) = \frac{3 \cdot 7}{3} - 7\ \ \]
\[f(x) = 0.\]
\[3)\ f(x) = 0,2:\ \ \ \ \ \ \ \]
\[\ 3x - 7 = 0,2\]
\[3x = 7,2\]
\[x = 2,4.\]