document.write( "Question 1018331: One end of diameter of a circle is (-2,-7)and its center is (3,0),find the coordinates of the other end.
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Algebra.Com's Answer #634490 by mathmate(429)\"\" \"About 
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\n" ); document.write( "Question:
\n" ); document.write( "One end of diameter of a circle is (-2,-7)and its center is (3,0),find the coordinates of the other end.
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\n" ); document.write( "Solution:
\n" ); document.write( "Since the centre is the mid-point of any diameter, we can use the mid-point formula to solve the problem.
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\n" ); document.write( "The mid-point formula is:
\n" ); document.write( "(xm,ym)=((x1+x2)/2,(y1+y2)/2)
\n" ); document.write( "where (xm,ym) are the coordinates of the mid point,
\n" ); document.write( "and (x1,y1), (x2,y2) are the coordinates of the two end-points of the diameter.
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\n" ); document.write( "Therefore
\n" ); document.write( "(x1,y1)=(-2,-7)
\n" ); document.write( "(xm,ym)=(3,0)
\n" ); document.write( "so
\n" ); document.write( "x1=-2
\n" ); document.write( "y1=-7
\n" ); document.write( "xm=3
\n" ); document.write( "ym=0
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\n" ); document.write( "Applying the formula:
\n" ); document.write( "xm=(x1+x2)/2,
\n" ); document.write( "3=(-2+x2)/2
\n" ); document.write( "(-2+x2)=2*3=6
\n" ); document.write( "x2=6+2=8
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\n" ); document.write( "ym=(y1+y2)/2
\n" ); document.write( "0=(-7+y2)/2
\n" ); document.write( "-7+y2=0
\n" ); document.write( "y2=7
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\n" ); document.write( "Therefore the coordinates of the other end is (8,7)
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\n" ); document.write( "Alternative method:
\n" ); document.write( "Since the centre is the mid-point of the diameter, we can use the fact that the change in x and y are the same between one end point and the centre, and the centre to the other end point.
\n" ); document.write( "So
\n" ); document.write( "endpoint=(-2,7)
\n" ); document.write( "centre=(3,0)
\n" ); document.write( "The increase in x from given endpoint to centre = (3-(-2))=5
\n" ); document.write( "The x-coordinate of the other end point is
\n" ); document.write( "3+5=8
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\n" ); document.write( "The increase in y from given endpoint to centre = (0-(-7))=7
\n" ); document.write( "The y-coordinate of the other end point is
\n" ); document.write( "0+7=7
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\n" ); document.write( "So the coordinates of the other end point is (8,7)
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