[tex]x - 2 \frac{15}{28} = 13 \frac{23}{28} \\ x = 13 \frac{23}{28} + 2 \frac{15}{28} \\ x = 15 \frac{38}{28} \\ x = 16 \frac{10}{28} \\ x = 16 \frac{5}{14} [/tex]