document.write( "Question 762677: a) show that the equation 0.25x squared - 0.7+ 1.5 =0 does not have any real roots.\r
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document.write( "b) the line y=2x - 5 and the curve xsquared + xy = 2 intersects at the point A and B, show that the equation to find the points A and B is givin by:
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document.write( "3xsquared - 5x - 2 = 0.\r
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document.write( "Hence find the coordinates of A and B. \n" );
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Algebra.Com's Answer #464119 by malglu(63)![]() ![]() ![]() You can put this solution on YOUR website! use the determinant b^2-4ac \n" ); document.write( "which is \n" ); document.write( "(-0.7)^2 - 4 x 0.25 x 1.5 \n" ); document.write( "this = -1.01 \n" ); document.write( "when the determinant is less then 0 then the roots are not real.\r \n" ); document.write( "\n" ); document.write( "the points A and B obviously are on both the line and the curve. to find them we neeed to put 2x -5 in the equation of the curve whenever it has y\r \n" ); document.write( "\n" ); document.write( "x^2 + (2x-5)x -2 =0\r \n" ); document.write( "\n" ); document.write( "i have then -2 on each side so i can equal the equation to 0. the equation is now \n" ); document.write( "x^2 + 2x^2 -5x -2=0 \n" ); document.write( "3x^2 -5x -2 =0\r \n" ); document.write( "\n" ); document.write( "now find the roots of this equation \n" ); document.write( "i used the formula to get x=2 and x= -1/3\r \n" ); document.write( "\n" ); document.write( "put these values into any of the original equtions to get the y co-ordinates.\r \n" ); document.write( "\n" ); document.write( "y=2x-5, so when x = 2 y = -1 and when x=-1/3 y=-17/3. these are the points A and B\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |