document.write( "Question 661589: Please help me figure out this problem: 2x^2+2y^2+16x+8y−32=0 is the equation of a circle with center (h,k) and radius r for: h, k, and r\r
\n" ); document.write( "\n" ); document.write( "I got 2(x^2-8x+16) + 2 (y^2 + 4y + 4) = 32 +16 +4\r
\n" ); document.write( "\n" ); document.write( "divide by 2: (x-4)^2 + (y+2)^2 = 26\r
\n" ); document.write( "\n" ); document.write( "(4, -2) and radius of sqrt 26 or 5.09901951\r
\n" ); document.write( "\n" ); document.write( "my homework page has confirmed that only -2 was correct. Where did I make a mistake? \n" ); document.write( "
Algebra.Com's Answer #411699 by lwsshak3(11628)\"\" \"About 
You can put this solution on YOUR website!
standard form of equation for a circle:
\n" ); document.write( "(x-h)^2+(y-k)^2=r^2, (h,k)=(x,y) coordinates of center, r=radius
\n" ); document.write( "..
\n" ); document.write( "2x^2+2y^2+16x+8y−32=0
\n" ); document.write( "complete the square:
\n" ); document.write( "2x^2+16x+2y^2+8y−32=0
\n" ); document.write( "2(x^2+8x+16)+2(y^2+4y+4)=32+32+8
\n" ); document.write( "2(x+4)^2+2(y+2)^2=72
\n" ); document.write( "divide by 2
\n" ); document.write( "(x+4)^2+(y+2)^2=36 (equation of given circle)
\n" ); document.write( "h=-4
\n" ); document.write( "k=-2
\n" ); document.write( "r=6
\n" ); document.write( " \n" ); document.write( "
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