document.write( "Question 985860: what is the correct statement for the quadratic equation y = 2x^2+x+7
\n" ); document.write( "1) has a maximum value because a>0
\n" ); document.write( "2) has a negative y - intercept
\n" ); document.write( "3) has no intercepts on the x-axis
\n" ); document.write( "4)has a discriminant that is more then zero
\n" ); document.write( "5) none of the above \n" ); document.write( "

Algebra.Com's Answer #606643 by Edwin McCravy(20055) $\"\"$ $\"About$

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document.write( "We can answer everything either from the graph or\r\n" );
document.write( "from the equation and the disriminant.\r\n" );
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\n" ); document.write( "1) has a maximum value because a > 0
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document.write( "If a quadratic equation has a > 0 it opens upward and has a minimum value.\r\n" );
document.write( "If a quadratic equation has a < 0 it opens downward and has a maximum value.\r\n" );
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document.write( "So (1) is false.\r\n" );
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\n" ); document.write( "2) has a negative y - intercept
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document.write( "If c > 0  the graph has a positive y-intercept\r\n" );
document.write( "If c < 0  the graph has a negative y-intercept  \r\n" );
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document.write( "The others depend on the discriminant:\r\n" );
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document.write( "If discriminant > 0 there are two x-intercepts\r\n" );
document.write( "If discriminant = 0 there is one x-intercept\r\n" );
document.write( "If discriminant < 0 there are no x-intercepts\r\n" );
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document.write( "Discriminant = b²-4ac = 1²-4(2)(7) = 1-56 = -55\r\n" );
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\n" ); document.write( "3) has no intercepts on the x-axis
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document.write( "That is true because the discriminant < 0\r\n" );
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\n" ); document.write( "4)has a discriminant that is more then zero
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document.write( "That's false because discriminant = -55\r\n" );
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document.write( "So the only correct answer is 3.\r\n" );
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document.write( "Let's graph it.\r\n" );
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document.write( " x | y\r\n" );
document.write( "-3 | 22\r\n" );
document.write( "-2 | 13\r\n" );
document.write( "-1 | 8\r\n" );
document.write( " 0 | 7\r\n" );
document.write( " 1 | 10\r\n" );
document.write( " 2 | 17\r\n" );
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document.write( "So from the graph we can tell: \r\n" );
document.write( "It has a minimum value.\r\n" );
document.write( "It has a positive y-intercept.\r\n" );
document.write( "It has no intercepts on the x-axis.\r\n" );
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document.write( "Edwin

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