document.write( "Question 203863: help needed:
\n" ); document.write( "Give points which are outside and pont which are inside of the circles in this equation: x^2+y^2+6x=0
\n" ); document.write( "p.s: could you please explain the solution for me that I can solve a group of questions like this ? Thank you:)
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Algebra.Com's Answer #153820 by Earlsdon(6294)\"\" \"About 
You can put this solution on YOUR website!
First get your equation into the standard form for a circle whose center is at (h, k) and whose radius is r.:
\n" ); document.write( "\"%28x-h%29%5E2%2B%28y-k%29%5E2+=+r%5E2\"
\n" ); document.write( "\"x%5E2%2By%5E2%2B6x+=+0\" Group the variables as shown below:
\n" ); document.write( "\"%28x%5E2%2B6x%29%2By%5E2+=+0\" Now \"complete-the-square\" in the x-variable by adding the square of half the x-coefficient to both sides of the equation. \"%286%2F2%29%5E2+=+9\"
\n" ); document.write( "\"%28x%5E2%2B6x%2B9%29%2By%5E2+=+0%2B9\" Factor the trinomial in x.
\n" ); document.write( "\"%28x%2B3%29%5E2%2By%5E2+=+9\" Compare this with the standard form for a circle:
\n" ); document.write( "\"%28x-h%29%5E2%2B%28y-k%29%5E2+=+r%5E2\"
\n" ); document.write( "The center of the circle is at (-3, 0) and the radius is 3.
\n" ); document.write( "It's probably easier to graph the circle then pick out the appropriate points inside and outside of the circle.
\n" ); document.write( "To graph the circle, you will need to solve your equation for y (you will get two solutions) then graph both solutions.
\n" ); document.write( "\"x%5E2%2By%5E2%2B6x+=+0\" Subtract \"x%5E2\" and \"6x\" from both sides.
\n" ); document.write( "\"y%5E2+=+-x%5E2-6x\" Take the square root of both sides.
\n" ); document.write( "\"y+=+sqrt%28-x%5E2-6x%29\" and \"y+=+-sqrt%28-x%5E2-6x%29\"
\n" ); document.write( "Now we'll graph these two solutions on the same grid:
\n" ); document.write( "\"graph%28400%2C400%2C-8%2C8%2C-8%2C8%2Csqrt%28-x%5E2-6x%29%2C-sqrt%28-x%5E2-6x%29%29\"
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