Chapter 7 - Functions and Graphs - 7.2 Domain and Range - 7.2 Exercise Set - Page 459: 58

$a.\quad-2$ $b.\quad-15$ $c.\quad-50$

$a.\quad $ $x=-1$ belongs to the interval $x\lt 3$, so we calculate its function value with $F(x)=2x$ $F(-1)=2(-1)=-2$ $b.\quad $ $x=3$ belongs to the interval $x\geq 3,$ so we calculate its function value with $F(x)=-5x$ $F(3)=-5(3)=-15$ $c.\quad $ $x=10$ belongs to the interval $x\geq 3$, so we calculate its function value with $x\geq 3,$ so we calculate its function value with $F(x)=-5x$ $F(10)=-5(10)=-50$