In the given figure. if AD $$\perp$$ BC, AC = 26 units, CD = 10 units, BC = 42 units, $$\angle DAC = x$$, and $$\angle B = y$$, then the value of $$\frac{6}{\cos x} - \frac{5}{\cos y} + 8 \tan y$$ is:

A

$$\frac{16}{9}$$

B

$$\frac{13}{6}$$

C

$$\frac{25}{4}$$

D

$$\frac{15}{7}$$