Trigonometry - compound angles

(1+ tanx) / (1-tanx) = 2

1+tanx = 2(1-tanx)

1+tanx = 2-2tanx

3tanx = 1

tanx = 1/3

tanx = tan18.4°(corr. to 3 sig. fig.)

x=180°n+18.4°

( 1 + tan x )/( 1 - tan x ) = 2
1 + tan x = 2 - 2 tan x
3tan x = 1
tan x = 1/3
x = 18.4 or 180 + 18.4 = 198.4