We have to solve the inequality
[tex]t-5\leq-7[/tex]To do that, we add the 5 to both sides of the inequality, then we have
[tex]\begin{gathered} t-5\leq-7 \\ t-5+5\leq-7+5 \\ t\leq-2 \end{gathered}[/tex]Then the solution to the inequality in interval notation is
[tex](-\infty,-2\rbrack[/tex]To graph the inequality we first graph the equation
[tex]t-5=-7[/tex]simplifying the equation we have
[tex]t=-2[/tex]This represents a vertical line that intersects with -2
Now we have to decide wich of the two semiplanes we have to choose to "color" that represents the solution of the inequality, since the solution was
[tex]t\leq-2[/tex]we color the semiplane to the left of the line