document.write( "Question 128866: (5-4i)(3+6i) \n" ); document.write( "
Algebra.Com's Answer #94249 by jim_thompson5910(35256)\"\" \"About 
You can put this solution on YOUR website!
\r
\n" ); document.write( "\n" ); document.write( "\"%285-4i%29%283%2B6i%29\" Start with the given expression\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Now let's FOIL the expression\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "Remember, when you FOIL an expression, you follow this procedure:\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"%28highlight%285%29-4i%29%28highlight%283%29%2B6i%29\" Multiply the First terms:\"%285%29%2A%283%29=15\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"%28highlight%285%29-4i%29%283%2Bhighlight%286i%29%29\" Multiply the Outer terms:\"%285%29%2A%286i%29=30i\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"%285%2Bhighlight%28-4i%29%29%28highlight%283%29%2B6i%29\" Multiply the Inner terms:\"%28-4i%29%2A%283%29=-12i\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"%285%2Bhighlight%28-4i%29%29%283%2Bhighlight%286i%29%29\" Multiply the Last terms:\"%28-4i%29%2A%286i%29=-24i%5E2\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"15%2B30i-12i-24i%5E2\" Now collect every term to make a single expression\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"18i-24i%5E2%2B15\" Now combine like terms\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"18i-24%28-1%29%2B15\" Replace \"i%5E2\" with \"-1\". Remember, \"i%5E2=-1\"\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"18i%2B24%2B15\" Multiply\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "\"39%2B18i\" Combine like terms\r
\n" ); document.write( "
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "---------------------\r
\n" ); document.write( "\n" ); document.write( "Answer:\r
\n" ); document.write( "\n" ); document.write( "So \"%285-4i%29%283%2B6i%29\" foils and simplifies to \"39%2B18i\"\r
\n" ); document.write( "
\n" ); document.write( "\n" ); document.write( "In other words, \"%285-4i%29%283%2B6i%29=39%2B18i\"\r
\n" ); document.write( "\n" ); document.write( "
\n" ); document.write( "
\n" );