document.write( "Question 1171491: prove that -1(a)=-a \n" ); document.write( "

Algebra.Com's Answer #796537 by math_helper(2461) $\"\"$ $\"About$

You can put this solution on YOUR website!


\n" );
document.write( "Look at -a first.\r
\n" );
document.write( "\n" );
document.write( "Add a:  -a + a = 0   (by the definition of the additive inverse)\r
\n" );
document.write( "
\n" );
document.write( "\n" );
document.write( "Look at -1(a) next.
\n" );
document.write( "Add a:  -1(a) + a
\n" );
document.write( "Factor:  = a(-1 + 1)
\n" );
document.write( "Simplify: = a(0) = 0\r
\n" );
document.write( "\n" );
document.write( "This has shown  -1(a) + a = -a + a,  thus  -1(a) = -a and the proof is
\n" );
document.write( "complete. \n" );
document.write( "

\n" );