document.write( "Question 553439: I need help solving this equation, we have been working on factoring and I can't seem to find a solution for this equation, please help! Thanks!\r
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document.write( "Solve: 6/(y-2)+7/(y-8)=(y-1)/(y-8) \n" );
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Algebra.Com's Answer #360835 by Theo(13342)![]() ![]() You can put this solution on YOUR website! your original equation is: \n" ); document.write( "6/(y-2) + 7/(y-8) = (y-1)/(y-8) \n" ); document.write( "multiply both sides of this equation by (y-2)(y-8) to get: \n" ); document.write( "6(y-8) + 7(y-2) = (y-1)(y-2) \n" ); document.write( "simplify to get: \n" ); document.write( "6y - 48 + 7y - 14 = y^2 - 3y + 2 \n" ); document.write( "simplify by combining like terms to get: \n" ); document.write( "13y - 62 = y^2 - 3y + 2 \n" ); document.write( "subtract 13y and add 62 to both sides of the equation to get: \n" ); document.write( "0 = y^2 - 16y + 64 \n" ); document.write( "commute to get: \n" ); document.write( "y^2 - 16y + 64 = 0 \n" ); document.write( "that's your quadratic equation which can now be factored to: \n" ); document.write( "(y-8)^2 = 0 which becomes: \n" ); document.write( "(y-8)(y-8) = 0 which yields: \n" ); document.write( "y = 8 \n" ); document.write( "that's your answer until you plug that answer back into the original equation. \n" ); document.write( "then you get a nasty surprise because x = 8 is undefined in the original equation because it makes the denominator equal to 0. \n" ); document.write( "that means that there is no real solution to your original equation. \n" ); document.write( "x = 8 is a good answer for y^2 - 16y + 64 because it does yield the root at x = 8. \n" ); document.write( "when you graph the quadratic equation, you get something that looks like this: \n" ); document.write( " \n" ); document.write( "note that i had to replace y with x in order to graph it. \n" ); document.write( "note that the graph of the equation crosses the x-axis at x = 8. \n" ); document.write( "that's the root of the quadratic equation. \n" ); document.write( "----- \n" ); document.write( "when you graph the original equation, you get something very different that looks like this: \n" ); document.write( " \n" ); document.write( "note that the graph does cross the x-axis at x = 8. \n" ); document.write( "the problem is that the value of y is undefined in the original equation when x = 8 resulting in what is called a hole. \n" ); document.write( "a hole is a gap in the value of y. \n" ); document.write( "you have values of y all around that spot, but you do not have a value for y when x = 8. \n" ); document.write( "note again that your original equation was expressed with the variable of y but that i changed y to x in order to be able to graph it. \n" ); document.write( "when you graph the equation, x is the independent variable and y is the dependent variable. \n" ); document.write( "that has something to do with the software only being able to recognize x on the horizontal axis and y on the vertical axis. \n" ); document.write( "if you were drawing the draph manually, then you could have assigned horizontal to z and vertical to z or any other letter. \n" ); document.write( "you do have an answer for your quadratic equation. \n" ); document.write( "that answer is 8. \n" ); document.write( "you do not have an answer for the original equation because x = 8 (rather y = 8) is not defined in the original equation.\r \n" ); document.write( " \n" ); document.write( " \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |