91影视

Let, $w$be the number of miles covered by walking and $r$be the number of miles covered by running by Mark.

Mark is increasing his exercise routine by running and walking at least $4$miles each day. So, the inequality is: $w+r鈮�4$.

His goal is to burn a minimum of $1500$calories from this exercise. Walking burns $270$calories per mile and running burns $650$calories per mile. So, the inequality is: $270w+650r鈮�1500$.

Therefore, the system of inequalities is: $\left\{\begin{array}{l}w+r鈮�4\\ 270w+650r鈮�1500\end{array}\right.$

Below is the graph of the system of inequalities:$\left\{\begin{array}{l}w+r鈮�4\\ 270w+650r鈮�1500\end{array}\right.$

As the point $(3,1)$is not in the double shaded region of the graph, so,Mark cannot meet his goal by walking $3$miles and running $1$mile.

As the point $(2,2)$is in the double shaded region of the graph, so, Mark can meet his goal by walking$2$miles and running$2$miles.