SOLUTION: if 9cos square A+ 3 cos A = 0where 90degrees<0<180degrees what is the value of A to the nearest 10th.

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Question 29856: if 9cos square A+ 3 cos A = 0where 90degrees<0<180degrees what is the value of A to the nearest 10th.
Answer by venugopalramana(3286) About Me  (Show Source):
You can put this solution on YOUR website!
9cos square A+ 3 cos A = 0
=3COS A(3COS A+1)=0
SO .....COS A = 0 ...HENCE A=90 ..IN 90degrees 3COS A +1 =0...OR...COS A =-1/3
A=180-70.5=109.5 DEGREES