document.write( "Question 753661: Given the equation y=x^2 + 16x + 8
\n" ); document.write( "I have to find the vertex and x intercept of this equation. I am using
\n" ); document.write( "x = -b/2a. In trying to complete the square my answers are x= -.5 and x= -15,5. Thus I have the x intercepts as (-.5,0) and (-15.5,0). I don't think those answers are right and I am confused about how to find the vertex.
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Algebra.Com's Answer #458504 by MathLover1(20850)\"\" \"About 
You can put this solution on YOUR website!
The vertex form of a parabola's equation is generally expressed as :
\n" ); document.write( "\"y=+a%28x-h%29%5E2%2Bk+\" where (\"h\",\"k\") is the vertex\r
\n" ); document.write( "\n" ); document.write( "write your equation in vertex form \r
\n" ); document.write( "\n" ); document.write( "\"y=x%5E2+%2B+16x+%2B+8\"..complete the square \r
\n" ); document.write( "\n" ); document.write( "\"y=%28x%5E2+%2B+16x%2B__%29+%2B+8\".....add \"64\" (because \"8%5E2=64\"and \"2%2A8=16\") and subtract \"64\"\r
\n" ); document.write( "\n" ); document.write( "\"y=%28x%5E2+%2B+16x%2B64%29-64+%2B+8\"\r
\n" ); document.write( "\n" ); document.write( "\"y=%28x+%2B+8%29%5E2-56\"...as you can see \"h=-8\" and \"k=-56\"\r
\n" ); document.write( "\n" ); document.write( "so, the vertex is at (\"h\",\"k\")=(\"-8\",\"-56\")\r
\n" ); document.write( "\n" ); document.write( "\"x-intercept\": to find them, set \"y=0\" and solve for \"x\"\r
\n" ); document.write( "\n" ); document.write( "\"0=%28x+%2B+8%29%5E2-56\"\r
\n" ); document.write( "\n" ); document.write( "\"56=%28x+%2B+8%29%5E2\"\r
\n" ); document.write( "\n" ); document.write( "\"sqrt%2856%29=x+%2B+8\"\r
\n" ); document.write( "\n" ); document.write( "\"sqrt%2856%29-8=x+\"\r
\n" ); document.write( "\n" ); document.write( "solutions:\r
\n" ); document.write( "\n" ); document.write( "\"7.48-8=x+\"\r
\n" ); document.write( "\n" ); document.write( "\"-0.52=x+\"\r
\n" ); document.write( "\n" ); document.write( "or\r
\n" ); document.write( "\n" ); document.write( "\"-7.48-8=x+\"\r
\n" ); document.write( "\n" ); document.write( "\"-15.48=x+\"\r
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