document.write( "Question 338934: how can you foil (a+b+c)(a+b+c) ? \n" ); document.write( "

Algebra.Com's Answer #242930 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
Use a substitution.
\n" ); document.write( "Let $\"D=b%2Bc\"$ .
\n" ); document.write( " $\"%28a%2Bb%2Bc%29%28a%2Bb%2Bc%29=%28a%2BD%29%28a%2BD%29\"$
\n" ); document.write( " $\"%28a%2Bb%2Bc%29%28a%2Bb%2Bc%29=a%5E2%2BaD%2BDa%2BD%5E2\"$
\n" ); document.write( " $\"%28a%2Bb%2Bc%29%28a%2Bb%2Bc%29=a%5E2%2B2aD%2BD%5E2\"$
\n" ); document.write( "Now substitute back,
\n" ); document.write( " $\"%28a%2Bb%2Bc%29%28a%2Bb%2Bc%29=a%5E2%2Ba%28b%2Bc%29%2B%28b%2Bc%29a%2B%28b%2Bc%29%5E2\"$
\n" ); document.write( " $\"%28a%2Bb%2Bc%29%28a%2Bb%2Bc%29=a%5E2%2Bab%2Bac%2Bab%2Bac%2Bb%5E2%2B2bc%2Bc%5E2\"$
\n" ); document.write( " $\"%28a%2Bb%2Bc%29%28a%2Bb%2Bc%29=a%5E2%2Bb%5E2%2Bc%5E2%2B2ab%2B2ac%2B2bc\"$
\n" ); document.write( " $\"%28a%2Bb%2Bc%29%28a%2Bb%2Bc%29=a%5E2%2Bb%5E2%2Bc%5E2%2B2%28ab%2Bbc%2Bac%29\"$ \r
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