Answer:
[tex]t\ge8[/tex]Chau has to trim trees for 8 hours or more to earn at least $39.
Explanation:
Let t represent the possible number of hours.
From the information in the question, we can go ahead set up the below inequality;
[tex]6t-9\ge39[/tex]Let's solve for t by adding 9 to both sides;
[tex]\begin{gathered} 6t-9+9\ge39+9 \\ 6t\ge48 \end{gathered}[/tex]Dividing both sides by 6, we'll have;
[tex]\begin{gathered} \frac{6t}{6}\ge\frac{48}{6} \\ t\ge8 \end{gathered}[/tex]We can see from the above that Chau has to trim trees for 8 hours or more to earn $39 or more.
