document.write( "Question 934410: The point P moves along an arc of a circle with centre E(2, 3). the arc of the circle passes through A(-2, 0) and B(5, k).
\n" ); document.write( "(a) Find
\n" ); document.write( "(i) the equation of the locus of the point P,
\n" ); document.write( "(ii) the values of k.
\n" ); document.write( "(b) The tangent of the circle at the point A intersects the y-axis at the point Q. Find the area of the triangle OAQ where Of is the origin.
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Algebra.Com's Answer #568915 by Fombitz(32388)\"\" \"About 
You can put this solution on YOUR website!
The general equation of a circle is,
\n" ); document.write( "\"%28x-h%29%5E2%2B%28y-k%29%5E2=R%5E2\"
\n" ); document.write( "\"%28x-2%29%5E2%2B%28y-3%29%5E2=R%5E2\"
\n" ); document.write( "Use A to get R.
\n" ); document.write( "\"%28-2-2%29%5E2%2B%280-3%29%5E2=R%5E2\"
\n" ); document.write( "\"16%2B9=R%5E2\"
\n" ); document.write( "\"R%5E2=25\"
\n" ); document.write( "\"R=5\"
\n" ); document.write( ".
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\n" ); document.write( ".
\n" ); document.write( "\"%28x-2%29%5E2%2B%28y-3%29%5E2=25\"
\n" ); document.write( "\"%285-2%29%5E2%2B%28k-3%29%5E2=25\"
\n" ); document.write( "\"9%2B%28k-3%29%5E2=25\"
\n" ); document.write( "\"%28k-3%29%5E2=16\"
\n" ); document.write( "\"k-3=+0+%2B-+4\"
\n" ); document.write( "\"k=3+%2B-+4\"
\n" ); document.write( "\"k=-1\" and \"k=7\"
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\n" ); document.write( ".\r
\n" ); document.write( "\n" ); document.write( "\"2%28x-2%29dx%2B2%28y-3%29dy=0\"
\n" ); document.write( "\"%28y-3%29dy=-%28x-2%29dx\"
\n" ); document.write( "\"dy%2Fdx=-%28x-2%29%2F%28y-3%29\"
\n" ); document.write( "At A,
\n" ); document.write( "\"dy%2Fdx=-%28-2-2%29%2F%280-3%29\"
\n" ); document.write( "\"dy%2Fdx=-%284%2F3%29\"
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\n" ); document.write( "The value of the derivative is equal to the slope of the tangent line.
\n" ); document.write( "Using the point-slope form of a line,
\n" ); document.write( "\"y-0=-%284%2F3%29%28x-%28-2%29%29\"
\n" ); document.write( "\"y=-%284%2F3%29%28x%2B2%29\"
\n" ); document.write( "So when \"x=0\"
\n" ); document.write( "\"y=-%284%2F3%29%282%29\"
\n" ); document.write( "\"y=-8%2F3\"
\n" ); document.write( "So know you know the base and height of the triangle.
\n" ); document.write( "\"A=%281%2F2%29%282%29%288%2F3%29\"
\n" ); document.write( "\"A=8%2F3\"
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