I need help solving please I don’t understand how to set up the problem thank you in advanced

Answer:
x = 5 unit
Step-by-step explanation:
The given figure represent the theorem of circle,
It two chords of circle intersect outside or inside when produce, then
AP × PB = DP × PC
SO , from given data we can find the X
Now, (X + 4) × 4 = (9 + 3) × 3
Or, X + 4 = [tex]\frac{12 times 3}{4}[/tex]
Or, X + 4 = [tex]\frac{36}{4}[/tex]
Or, X = 9 - 4
∴ X = 5 unit