document.write( "Question 1106619: Find the equation of a circle passing through two points (-4,1) and (4,5) whose centre lies on the straight line 2x-y=1 \n" ); document.write( "
Algebra.Com's Answer #721622 by dkppathak(439)\"\" \"About 
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Find the equation of a circle passing through two points (-4,1) and (4,5) whose centre lies on the straight line 2x-y=1
\n" ); document.write( "(X-h)^2 +(y-k)^2=r^2
\n" ); document.write( "the circle passing through -4,1
\n" ); document.write( "(-4-h)^2 +(1-k)^2=r^2 ---(1)
\n" ); document.write( "the circle passing through 4,5
\n" ); document.write( "(4-h)^2 +(5-k)^2=r^2 ---(2) 1 and 2 both are equal
\n" ); document.write( "(-4-h)^2 +(1-k)^2 =(4-h)^2 +(5-k)^2
\n" ); document.write( "16+h^2+8h+1+k^2-2k=16+h^2-8h+25+k^2-10k
\n" ); document.write( "16h+8k-24=0
\n" ); document.write( "2h+k=3 (3)
\n" ); document.write( "center lies on line 2x-y=1 center h,k lies and satisfy the line
\n" ); document.write( "2h-k=1 (4) by solving 3, 4 we will get h=1 and k=1
\n" ); document.write( "by putting the value of h and k in equation 1 we will get radius =5
\n" ); document.write( "equation of circle will bw
\n" ); document.write( "(x-1)^2 +(y-1)^2=25
\n" ); document.write( "or
\n" ); document.write( "x^2+y^2-2x-2y-23=0
\n" ); document.write( " \n" ); document.write( "
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