Respuesta :

Answer:

10

Step-by-step explanation:

By intersecting secants theorem:

[tex]3x = \frac{1}{2} (4x + 50 - 30) \\ 6x = 4x + 20 \\ 6x - 4x = 20 \\ 2x = 20 \\ x = \frac{20}{2} \\ x = 10[/tex]