Posted by Cynthia on Friday, August 3, 2012 at 3:17pm.
Solve tan2 x + tan x – 1 = 0 for the principal value(s) to two
decimal places.
Please Explain

Trigonometry  Cynthia, Friday, August 3, 2012 at 3:19pm
* Solve tan^2x + tanx1=0 for the principal value(s) to two decimal places.

Trigonometry  MathMate, Friday, August 3, 2012 at 3:38pm
Let y=tan(x)
y²+y1=0
use quadratic formula
y=(1±√(5))/2
or
tan(x)=(1±√(5))/2
find tan^{1}(1±√(5))/2 using your calculator.