document.write( "Question 916822: I really need help understanding this ;/\r
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document.write( " What are the zero(s) of the function f(x) = the quantity of 5 x squared minus 25 x, all over x? \n" );
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Algebra.Com's Answer #556311 by Theo(13342)![]() ![]() You can put this solution on YOUR website! equation is y = (5x^2 + x)/x \n" ); document.write( "set y = 0 to get: \n" ); document.write( "(5x^2 + x)/x = 0 \n" ); document.write( "multiply both sides of the equation by x to get: \n" ); document.write( "5x^2 + x = 0 \n" ); document.write( "this is a quadratic equation that you can factor using any of the methods that work. \n" ); document.write( "i'll use the quadratic formula. \n" ); document.write( "since the eqaution is in standard form of ax^2 + bx + c = 0, you can get the values of a, b, and c as follows: \n" ); document.write( "a = 5 \n" ); document.write( "b = 1 \n" ); document.write( "c = 0 \n" ); document.write( "the quadratic formula is x = (-b +/- sqrt(b^2-4ac))/(2a) \n" ); document.write( "replace a with 5 and b with 1 and c with 0 and you will get: \n" ); document.write( "x = 0 or x = -1/5 \n" ); document.write( "those are your possible solutions. \n" ); document.write( "you have to confirm that they are good by replacing x with them in the original equation to see if the equation is true. \n" ); document.write( "always confirm using the original equation or expression. \n" ); document.write( "the original equation is (5x^2 + x)/x = 0 \n" ); document.write( "when x = 0, the original equation of (5x^2 + x)/x = 0 becomes (0/0) = 0 which becomes undefined = 0 which is not true. \n" ); document.write( "the expression 0/0 is undefined because the denominator is equal to 0. \n" ); document.write( "x = 0 is therefore not a solution to this problem. \n" ); document.write( "when x = -1/5, the original equation of (5x^2 + x)/x = 0 becomes (5*(1/25 - 1/5) / (1/5) = 0 which becomes (1/5 - 1/5) / (1/5) = 0 which becomes 0 / (1/5) = 0 which becomes 0 = 0 which is true. \n" ); document.write( "x = -1/5 is therefore the only solution to this problem.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |