SOLUTION: How do you solve: 3tan^2(x)+4sec(x)=-4

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Question 454345: How do you solve:
3tan^2(x)+4sec(x)=-4
Answer by lwsshak3(11628) About Me  (Show Source):
You can put this solution on YOUR website!
How do you solve:
3tan^2(x)+4sec(x)=-4
0 ..
3tan^2(x)+4sec(x)=-4
Using identity: tan^(x)+1=sec^2(x)
3(sec^2(x)-1)+4sec(x)=-4
3sec^2(x)-3+4sec(x)=-4
3sec^2(x)-3+4sec(x)+4=0
3sec^2(x)+4sec(x)+1=0
(3sec(x)+1)(sec(x)+1)=0
sec(x)=-1/3
cos(x)=-3 (reject, (-1 < cos(x) <1)
sec(x)=-1
cos(x)=-1
x=180º or π radians