document.write( "Question 40422: -2x^2+7x-10<=(-3)x+2\r
\n" ); document.write( "\n" ); document.write( "Possible answers\r
\n" ); document.write( "\n" ); document.write( "a. (-inf,-3) U (-2,+inf)
\n" ); document.write( "b. (-inf,2) U (3, inf)
\n" ); document.write( "c. (-3,-2)
\n" ); document.write( "d. (2,3)
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Algebra.Com's Answer #25778 by fazlerabbi(9)\"\" \"About 
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\"-2%2Ax%5E2%2B7%2Ax-10+%3C=+%28-3%29%2Ax%2B2\" given
\n" ); document.write( "\"-2%2Ax%5E2%2B10%2Ax-10+%3C=+2\" subtracted (-3)*x from both sides
\n" ); document.write( "\"-x%5E2%2B5%2Ax-5+%3C=+1\" multiplied both sides by 1/2
\n" ); document.write( "\"-x%5E2%2B5%2Ax-6+%3C=+0\" subtracted 1 from both sides
\n" ); document.write( "\"x%5E2-5%2Ax%2B6+%3E=+0\" multiplied both sided by -1\r
\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)
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