document.write( "Question 440161: A.Find the equation of the quadratic function in standard form
\n" ); document.write( "vertex (0, 18) ; passing through (-3, 0)
\n" ); document.write( " A. y = -2x2 + 18
\n" ); document.write( "B. y = -2x2 - 18
\n" ); document.write( "C. y = x2 + 18
\n" ); document.write( "D. y = 18x2 + 18 \r
\n" ); document.write( "\n" ); document.write( "B. 6. Write the quadratic function in the vertex form.
\n" ); document.write( "y = -3x^2 - 30x - 71
\n" ); document.write( " A. y = 3(x + 5) 2 + 4
\n" ); document.write( "B. y = -3(x - 5) 2 + 4
\n" ); document.write( "C. y = (x + 5) 2 + 4
\n" ); document.write( "D. y = -3(x + 5) 2 + 4
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Algebra.Com's Answer #304136 by ewatrrr(24785) $\"\"$ $\"About$

You can put this solution on YOUR website!

 
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document.write( "Hi
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document.write( "Using the vertex form of a parabola,  where(h,k) is the vertex
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document.write( "vertex (0, 18) 
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document.write( " y = ax^2 + 18      |passing through (-3, 0) 
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document.write( " 0 = a*9 + 18
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document.write( "-18 = 9a
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document.write( "-2 = a
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document.write( " y = -2x^2 + 18\r
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document.write( "Write the quadratic function in the vertex form. 
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document.write( "y = -3x^2 - 30x - 71    |Completing the square to do so
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document.write( "y = -3[x^2 +10x] - 71 
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document.write( "y = -3[(x+5)^2 -25] - 71
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document.write( "y = -3(x+5)^2 + 75 - 71
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document.write( "y = -3(x+5)^2 + 4
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