document.write( "Question 202800: 3x^2+3y^2-24x-12y-15=0 Graph the circle using (h,k) and R find the intercepts if any \n" ); document.write( "
Algebra.Com's Answer #152971 by Earlsdon(6294)\"\" \"About 
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\"3x%5E2%2B3y%5E2-24x-12y-15+=+0\" Divide both sides by 3.
\n" ); document.write( "\"x%5E2%2By%5E3-8x-4y+-5+=+0\" Group the x- and y-terms as shown:
\n" ); document.write( "\"%28x%5E2-8x%29%2B%28y%5E2-4y%29-5+=+0\" Add 5 to both sides.
\n" ); document.write( "\"%28x%5E2-8x%29%2B%28y%5E2-4y%29+=+5\" Complete the square in both the x-terms and the y-terms.
\n" ); document.write( "\"%28x%5E2-8x%2B16%29%2B%28y%5E2-4y%2B4%29+=+5%2B16%2B4\" Factor the left groups ans simplify the right side.
\n" ); document.write( "\"%28x-4%29%5E2%2B%28y-2%29%5E2+=+25\" Compare with the standard form for a circle with center at (h, k) and radius r.
\n" ); document.write( "\"%28x-h%29%5E2%2B%28y-k%29%5E2+=+r%5E2\"
\n" ); document.write( "The center is at (4, 2) and the radius is 5.
\n" ); document.write( "To graph this circle, we will have to solve this equation for y and the graph each of the two solutions separately.
\n" ); document.write( "\"%28x-4%29%5E2%2B%28y-2%29%5E2+=+25\" Subtract \"%28x-4%29%5E2\" from both sides.
\n" ); document.write( "\"%28y-2%29%5E2+=+-%28x-4%29%5E2%2B25\" Simplify the right side.
\n" ); document.write( "\"%28y-2%29%5E2+=+-%28x%5E2-8x%2B16%29%2B25\"
\n" ); document.write( "\"%28y-2%29%5E2+=+-x%5E2%2B8x-16%2B25\"
\n" ); document.write( "\"%28y-2%29%5E2+=+-x%5E2%2B8x%2B9\" Take the square root of both sides.
\n" ); document.write( "\"y-2+=+sqrt%28-x%5E2%2B8x%2B9%29\" The right side should have a + or - sign in front. Add 2 to both sides.
\n" ); document.write( "\"y+=+2%2B-sqrt%28-x%5E2%2B8x%2B9%29\" Now graph both of these solutions.
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\n" ); document.write( "The y-intercepts are: (0, 5) and (0, -1)
\n" ); document.write( "The x-intercepts are: (8.58, 0) and (-0.58, 0)
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