document.write( "Question 602355: Hello,
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document.write( "would you pls check if my answer is correct?
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document.write( "1)Without drawing the graph of the equations, determine how many points the parabola has in common with the x-axis and whether its vertex lies above, on, or below the x-axis.
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document.write( " a. y = 3x^2 – 12x + 12
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document.write( " b. y = –2x^2 + x + 3
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document.write( "My answer : a. 1 point in common; vertex on x-axis
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document.write( " b. 2 points in common; vertex above x-axis
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document.write( "Thanks a lot,
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document.write( " H.H
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document.write( "P.S.:This is my 2nd submission for this question. \n" );
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Algebra.Com's Answer #380208 by Alan3354(69443)![]() ![]() You can put this solution on YOUR website! 1)Without drawing the graph of the equations, determine how many points the parabola has in common with the x-axis and whether its vertex lies above, on, or below the x-axis. \n" ); document.write( " a. y = 3x^2 – 12x + 12 \n" ); document.write( "Find the discriminant \n" ); document.write( "D = b^2 - 4ac \n" ); document.write( "D = (-12)^2 - 4*3*12 \n" ); document.write( "D = 0 --> 1 real number solution \n" ); document.write( "It's actually 2 solutions that are equal, but that makes one point on the x-axis. \n" ); document.write( "----------------- \n" ); document.write( " b. y = –2x^2 + x + 3 \n" ); document.write( "D = 1 - 4*-2*3 \n" ); document.write( "D = 25 \n" ); document.write( "D > 0 --> 2 real solutions, 2 crossings of the x-axis \n" ); document.write( "------------ \n" ); document.write( " \n" ); document.write( "My answer : a. 1 point in common; vertex on x-axis \n" ); document.write( "Correct. \n" ); document.write( "============================================ \n" ); document.write( " b. 2 points in common; vertex above x-axis \n" ); document.write( "2 points. The coefficient of the x^2 terms is negative, so it opens downward. \n" ); document.write( "--> vertex above the x-axis \n" ); document.write( "Correct. \n" ); document.write( " |