document.write( "Question 40422: -2x^2+7x-10<=(-3)x+2\r
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document.write( "Possible answers\r
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document.write( "a. (-inf,-3) U (-2,+inf)
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document.write( "b. (-inf,2) U (3, inf)
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document.write( "c. (-3,-2)
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document.write( "d. (2,3) \n" );
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Algebra.Com's Answer #25778 by fazlerabbi(9)![]() ![]() ![]() You can put this solution on YOUR website! \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( "Factoring left side yields \n" ); document.write( "(x-3)(x-2) >= 0\r \n" ); document.write( "\n" ); document.write( "The values of x for which x-2=0 or x-3=0 are x=2 and x=5. These points divide the coordinate line into three intervals, \n" ); document.write( " (-inf,2], (2,3) and [3, +inf)\r \n" ); document.write( "\n" ); document.write( "We need to check points of which of these three intervals give positive sign for the product (x-3(x-2). We shall choose arbitrary points on each of these intervals to determine the sign; these points are called test points. Lets say 1, 2.5 and 4 will be the test points for intervals (-inf,2], (2,3) and [3, +inf) respectively.\r \n" ); document.write( "\n" ); document.write( "For interval (-inf,2] with test point 1 sign of (x-2)(x-3) is (-)(-) = + \n" ); document.write( "For interval (2,3) with test point 2.5 sign of (x-2(x-3) is (+)(-) = - \n" ); document.write( "For interval [3,+inf)with test point 4 sign of (x-2(x-3) is (+)(+) = +\r \n" ); document.write( "\n" ); document.write( "The pattern of signs suggest that the solution set is \n" ); document.write( "(-inf,2] U [3,+inf) \n" ); document.write( " \n" ); document.write( " |