document.write( "Question 387723: In solving the equation (x 1)(x 2) = 30, Eric stated that the solution would be \n" );
document.write( "x 1 = 30 => x = 31 \n" );
document.write( "or \n" );
document.write( "x 2) = 30 => x = 32 \n" );
document.write( "(x-2)(x-1)=30,x^2-2x-x+2=30,x^2-3x+2-30=0since x^2-3x-28=0 by factorization x^2+4x-7x-30=0,x(x+4)-7(x+4)=0 thrfr (x-7)(x+4)=0hence x=7 \n" );
document.write( "However, at least one of these solutions fails to work when substituted back into the original equation. Why is that? Please help Eric to understand better; solve the problem yourself, and explain your reasoning. \n" );
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