document.write( "Question 970912: y+x^2=-(8x+23) Write in vertex form and find axis of symmetry \n" ); document.write( "
Algebra.Com's Answer #593523 by Boreal(15235)\"\" \"About 
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y+x^2=-(8x+23) \r
\n" ); document.write( "\n" ); document.write( "y=-x^2-8x-23 = -(x^2+8x+23)\r
\n" ); document.write( "\n" ); document.write( "Complete the square -(x^2+8x +16). Have added -16 to the equation, have to add 16 to the constant outside, now so -23 +16 =-7\r
\n" ); document.write( "\n" ); document.write( "y=-(x+4)^2-7\r
\n" ); document.write( "\n" ); document.write( "Let's check this.
\n" ); document.write( "y= - {x^2+8x +16)-7 This is -x^2-8x-23, which is what we had. \r
\n" ); document.write( "\n" ); document.write( "a=-1, the coefficient of x.\r
\n" ); document.write( "\n" ); document.write( "The vertex x value is -b/2a = - (-8)/(-2) =-4\r
\n" ); document.write( "\n" ); document.write( "THE AXIS OF SYMMETRY IS THE LINE X= -4\r
\n" ); document.write( "\n" ); document.write( "If x= -4 y=-7\r
\n" ); document.write( "\n" ); document.write( "Vertex form y= a (x-h)^2 +k
\n" ); document.write( "y = -1(x+4)^2 -7\r
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\n" ); document.write( "\n" ); document.write( "\"graph+%28300%2C300%2C-10%2C10%2C-100%2C100%2C-x%5E2-8x-23%29\"\r
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