Answer:
x = - 12, 3
Step-by-step explanation:
By tangent secant theorem:
[tex]x(x + 9) = {6}^{2} \\ \\ {x}^{2} + 9x = 36 \\ \\ {x}^{2} + 9x - 36 = 0 \\ \\ {x}^{2} + 12x - 3x - 36 = 0 \\ \\ x(x + 12) - 3(x + 12) = 0 \\ \\ (x + 12)(x - 3) = 0 \\ \\ x + 12 = 0, \: \: x - 3 = 0 \\ \\ x = - 12, \: \: x = 3 \\ \\ [/tex]
