Answer:
13
Step-by-step explanation:
By angle bisector property:
[tex] \frac{28}{49} = \frac{12}{2x + 7 - 12} \\ \\ \frac{4}{7} = \frac{12}{2x - 5} \\ \\ 4(2x - 5) = 12 \times 7 \\ \\ 8x - 20 = 84 \\ \\ 8x = 84 + 20 \\ \\ 8x = 104 \\ \\ x = \frac{104}{8} \\ \\ x = 13[/tex]
