To create the graph of the equation C=20h+50, we use positive values since we are counting hours:
[tex]\begin{gathered} h=0 \\ \Rightarrow C=20\cdot0+50=50 \\ h=1 \\ \Rightarrow C=20\cdot1+50=20+50=70 \\ h=2 \\ \Rightarrow C=20\cdot2+50=40+50=90 \\ h=3 \\ \Rightarrow C=20\cdot3+50=60+50=110 \\ h=4 \\ \Rightarrow C=20\cdot4+50=80+50=130 \end{gathered}[/tex]Now we can make the graph using the points (0,50), (1,70) and so on:
