document.write( "Question 30011: How do i do 4/x-3 + 2x/x squared - 9 = 1/x+3 \n" ); document.write( "
Algebra.Com's Answer #16756 by sdmmadam@yahoo.com(530) ![]() You can put this solution on YOUR website! 4/x-3 + 2x/x squared - 9 = 1/x+3 \n" ); document.write( "4/(x-3) + 2x/(x^2-9) = 1/(x+3)----(1) \n" ); document.write( "Observe that (x^2-9) = (x+3)(x-3) \n" ); document.write( "using formula a^2-b^2 = (a+b)(a-b)and here a = x and b = 3 \n" ); document.write( "Multliplying (1) through out by (x^2-9) \n" ); document.write( "(divide the lcm of by each of the drs and multiply the answer by the corresponding nr and give the sign given between the terms. \n" ); document.write( "4(x+3)+2x =(x-3) \n" ); document.write( "4x+12+2x=x-3 \n" ); document.write( "(4x+2x-x)=-3-12 (grouping like terms, changing sign while changing side) \n" ); document.write( "5x=-15 \n" ); document.write( "x =-15/5 = -3 \n" ); document.write( "Answer: x =-3 THIS IS WRONG \n" ); document.write( "Why? Because division by zero is not defined(as zero does not have mulitplicative inverse) \n" ); document.write( "Note: If the problem is say like this: \n" ); document.write( "4/(x-3) - 2x/(x^2-9) = 1/(x+3)----(1) \n" ); document.write( "Multliplying (1) through out by (x^2-9) \n" ); document.write( "4(x+3)-2x =(x-3) \n" ); document.write( "4x+12-2x=x-3 \n" ); document.write( "(4x-2x-x)=-3-12 (grouping like terms, changing sign while changing side) \n" ); document.write( "x=-15 \n" ); document.write( "x =-15 \n" ); document.write( "Answer: x =-15 \n" ); document.write( "Verification: x = -15 in (1) holds \n" ); document.write( "LHS = -1/12 = RHS\r \n" ); document.write( "\n" ); document.write( " \n" ); document.write( " |