document.write( "Question 966798: Find all angles, 0≤θ<360, that satisfy the equation below, to the nearest 10th of a degree.
\n" ); document.write( "2cos2θ+9=3cosθ+8 \n" ); document.write( "

Algebra.Com's Answer #590891 by lwsshak3(11628) $\"\"$ $\"About$

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Find all angles, 0≤θ<360, that satisfy the equation below, to the nearest 10th of a degree.
\n" ); document.write( "2cos2θ+9=3cosθ+8
\n" ); document.write( "***
\n" ); document.write( " $\"2cos%282x%29%2B9=3cosx%2B8\"$
\n" ); document.write( " $\"2%28cos%5E2%28x%29-sin%5E2%28x%29%29-3cosx%2B1=0\"$
\n" ); document.write( " $\"2%28cos%5E2%28x%29%29-%281-cos%5E2%28x%29%29-3cosx%2B1=0\"$
\n" ); document.write( " $\"2cos%5E2%28x%29-2%2B2cos%5E2%28x%29-3cosx%2B1=0\"$
\n" ); document.write( " $\"4cos%5E2%28x%29-3cosx-1=0\"$
\n" ); document.write( "(4cosx+1)(cosx-1)=0
\n" ); document.write( "..
\n" ); document.write( "4cosx+1=0
\n" ); document.write( "cosx=-1/4
\n" ); document.write( "x=104.5˚, 255.5˚
\n" ); document.write( "or
\n" ); document.write( "cosx+1=0
\n" ); document.write( "cosx=-1
\n" ); document.write( "x=180˚ \n" ); document.write( "

\n" );