Answer:
[tex]\large\boxed{f(-3)=3.6}[/tex]
Step-by-step explanation:
[tex]f(x)=0.6(3-x)\\\\f(-3)\to\text{Put x = -3 to the equation of a function:}\\\\f(-3)=0.6(3-(-3))=0.6(3+3)=0.6(6)=3.6[/tex]
