document.write( "Question 409413: In solving the equation (x + 2)(x – 2) = 32, Eric stated that the solution would be
\n" ); document.write( "x + 2 = 32 => x = 30
\n" ); document.write( "or
\n" ); document.write( "(x – 2) = 32 => x = 34
\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.
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Algebra.Com's Answer #288232 by jsmallt9(3758)\"\" \"About 
You can put this solution on YOUR website!
There is no special product rule for 32. There are an infinite number of products that can equal 32.

\n" ); document.write( "But there is a special product rule for 0. If a product is zero, then one (or more) of the factors must be zero. So we need to manipulate the equation so it is a product that equals zero.

\n" ); document.write( "First we simplify the left side:
\n" ); document.write( "\"x%5E2-4+=+32\"
\n" ); document.write( "Next we make one side zero. Subtracting 32 from each side we get:
\n" ); document.write( "\"x%5E2-36+=+0\"
\n" ); document.write( "Now we factor. This is a difference of squares so it is easy to factor:
\n" ); document.write( "(x+6)(x-6) = 0
\n" ); document.write( "With this product that equals zero we know that one of the factors must be zero. So:
\n" ); document.write( "x+6 = 0 or x-6 = 0
\n" ); document.write( "Solving each of these we get:
\n" ); document.write( "x = -6 or x = 6
\n" ); document.write( "So there are two solutions to the original equation.
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