document.write( "Question 680803: find the vertex, any intercepts &the symmetric line?\r
\n" ); document.write( "\n" ); document.write( "1. f(x)=x^2+10x+9 \n" ); document.write( "

Algebra.Com's Answer #422467 by mananth(16946) $\"\"$ $\"About$

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f(x)=x^2+10x+9\r
\n" ); document.write( "\n" ); document.write( "y= x^2+10x+9\r
\n" ); document.write( "\n" ); document.write( "x coordinate of vertex = -b/2a= -10/2= -5\r
\n" ); document.write( "\n" ); document.write( "plug x= 5 in the equation\r
\n" ); document.write( "\n" ); document.write( "x^2+10x+9=y
\n" ); document.write( "(-5)^2+10(-5)+9=y
\n" ); document.write( "y=-16\r
\n" ); document.write( "\n" ); document.write( "Vertex(-5,-16)\r
\n" ); document.write( "\n" ); document.write( "The x intercept occurs when y=0, make the equation = 0 and solve for x
\n" ); document.write( "x^2 +10x+9 = 0
\n" ); document.write( "Factor
\n" ); document.write( "(x+9)(x+1) = 0
\n" ); document.write( "x = -9 and x = -1, these are the x intercepts
\n" ); document.write( ":
\n" ); document.write( "y intercept occurs when x=0, substitute 0 for x in the equation, and find y
\n" ); document.write( "y = 0^2 - 10(0) + 9
\n" ); document.write( "y = 9; :
\n" ); document.write( "Axis of symmetry x = -b/2a= -10/2=-5\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "x=-5 is the axis of symmetry. \n" ); document.write( "

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