document.write( "Question 436189: the parabola which is the graph of the function f: y= ax^2+bx+c, b>0,c<0 does not have any common point with the x-axis the top of this parabola lies in the same quadrant as the point with the coordinates A. {-1,-1} B.{-3,2} C.{2,-2} D. {1,1} AND PROVE THE ANSWER \n" ); document.write( "

Algebra.Com's Answer #301991 by richard1234(7193) $\"\"$ $\"About$

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Since $\"c+%3C+0\"$ , then $\"y%280%29+%3C+0\"$ , so the entire parabola must be contained within the third and fourth quadrants. Hence, $\"a+%3C+0\"$ .\r
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\n" ); document.write( "\n" ); document.write( "The vertex of the parabola occurs at $\"x+=+-b%2F2a\"$ . Since b is positive and a is negative, $\"-b%2F2a\"$ will be positive. The vertex has a positive x-coordinate and a negative y-coordinate, so it lies in the fourth quadrant, and choice C is correct. \n" ); document.write( "

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