document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=502372>Question 502372</A>: <I><SPAN STYLE=\"word-break: break-all;\"> . Simplify the following product of complex numbers.<BR>\n" );
document.write( "(-1 + 3i) • (-9 – 7i)<BR>\n" );
document.write( "can someone explain this to me </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #338823 by </B><A HREF=/tutors/aboutme.mpl?userid=geetha_rama><B>geetha_rama(94)</B></A><img src=\"/images/stars/stars-08.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=geetha_rama><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/images/nopicture.jpg><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=338823\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> (-1+3i) * (-9 - 7i)<BR>\n" );
document.write( "= -1*-9 + 3i*(-9) -1*(-7i) + (3i)*(-7i)<BR>\n" );
document.write( "= 9 -27i + 7i -21i^2<BR>\n" );
document.write( "= 9 -20i + 21 (since i^2 = -1)<BR>\n" );
document.write( "= 30 -20i<BR>\n" );
document.write( "= 10* (3 -2i) </SPAN>\n" );
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