Evaluating Functions - Algebra

Determine output values given input values

Determine input values given output values

Evaluate: to determine the value of something

Function: a relation in which each element of the domain is mapped to (paired with) exactly one element of the range

Input: the value that is transformed by a process and becomes an output

Output: The result of an input that has been transformed by a process

 $f\left(x\right)=\frac{1}{3}x-2$  

Determine the input that would give an output value of -2/3

 $-\frac{2}{3}=\frac{1}{3}x-2$  

 $\left(\frac{6}{3}\right)+\left(-\frac{2}{3}\right)=\frac{1}{3}x-\left(\frac{6}{3}\right)+\left(\frac{6}{3}\right)$  

 $\frac{4}{3}=\frac{1}{3}x$  

 $3\times\frac{4}{3}=\frac{1}{3}x\times3$  

 $x=4$