document.write( "Question 1179671: For the equation, identify the equation of the axis of symmetry, the coordinates of the vertex, the y-intercept, the zeros, and the maximum or minimum values.\r
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document.write( "1. y = -2(x - 3) 2 + 9 \n" );
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Algebra.Com's Answer #809239 by Boreal(15235)![]() ![]() You can put this solution on YOUR website! The vertex is at (-h, k), which would be x=3, y=9 or (3, 9) \n" ); document.write( "The axis of symmetry is therefore at x=3. \n" ); document.write( "the y-intercept is where x=0, and that is -2(9)+9=-9 so (0, -9) \n" ); document.write( "The maximum value for this convex upward parabola is when x=3 and that has already been shown to have y=9. \n" ); document.write( "The minimum values are at -oo. \n" ); document.write( "For the zeros, let y=0, \n" ); document.write( "then -2(x-3)^2=-9 \n" ); document.write( "or (x-3)^2=9/2 \n" ); document.write( "x-3=+/- 3(sqrt(2)/2 \n" ); document.write( "so the zeros are 3+/- (3/2) sqrt (2) \n" ); document.write( "-- \n" ); document.write( "Can check by writing it in standard form \n" ); document.write( "y=-2x^2+12x-18+9; -2x^2+12x-9=0, or 2x^2-12x+9=0 \n" ); document.write( "x= (1/4)(12+/-sqrt(144-72)) or (1/4)(12+/-6 sqrt(2)) \n" ); document.write( "roots are 3 +/- (3/2) sqrt(2) \n" ); document.write( "- \n" ); document.write( " |