Answer
(a) $f(-5)=-10$
(b) $f(-1)=-2$
(c) $f(0)=-1$
(d) $f(3)=2$
Work Step by Step
To evaluate the piecewise-defined function, identify the 'piece' of the function that covers the given value of $x$. Then substitute, the given value of $x$.
(a) $f(-5)$
For $x=-5$ the function is defined by $2x$.
Thus, $f(-5) = 2(-5)=-10$
(b) $f(-1)$
For $x=-1$ the function is defined by $2x$.
Thus, $f(-1) = 2(-1)=-2$
(c) $f(0)$
For $x=0$ the function is defined by $x-1$.
Thus, $f(0) = 0-1=-1$
(d) $f(3)$
For $x=-5$ the function is defined by $x-1$.
Thus, $f(3) = 3-1=2$
