document.write( "Question 578748: What is ( 7-4i/9+2i) \n" ); document.write( "

Algebra.Com's Answer #370756 by dfrazzetto(283) $\"\"$ $\"About$

You can put this solution on YOUR website!
To get rid of the complex term in the denominator, multiply top and bottom by the conjugate (9-2i)\r
\n" ); document.write( "\n" ); document.write( " $\"%287-4i%29%2F%289%2B2i%29+%2A+%289-2i%29%2F%289-2i%29\"$ \r
\n" ); document.write( "\n" ); document.write( "That gives us 81 - 4(i^2) = 81 + 4 = 85 in the denominator\r
\n" ); document.write( "\n" ); document.write( "In the numerator, use Use FOIL:\r
\n" ); document.write( "\n" ); document.write( "(7-4i)(9-2i) = 63 -14i -36i +8i^2; i^2=-1, so:\r
\n" ); document.write( "\n" ); document.write( "= 63 - 50i - 8 = 55 - 50i\r
\n" ); document.write( "\n" ); document.write( " $\"%2855-50i%29%2F%2885%29\"$ Divide through by 5\r
\n" ); document.write( "\n" ); document.write( " $\"%2811-10i%29%2F%2817%29\"$ \n" ); document.write( "

\n" );