Answer
domain: $(-\infty, +\infty)$
range: $(-\infty, +\infty)$
Refer to the graph below.
Work Step by Step
Find the x-intercept by setting $f(x)$ or $y$ to zero, then solve for $x$.
$f(x) = -x+4
\\0=-x+4
\\0+x=-x+4+x
\\x=4$
The x-intercept is $(4, 0)$.
Find the y-intercept by setting $x=0$ then solving for $y$.
$f(x)=-x+4
\\f(x) = -0+4
\\f(x)=4$
The y-intercept is $(0,4)$.
Plot the intercepts and connect them using a line. The point $(2, 2)$ can be used as a check point.
(Refer to the graph in the answer part above.)
The graph covers all x-values and all y-values.
Thus, the given function has:
domain: $(-\infty, +\infty)$
range: $(-\infty, +\infty)$
