document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=549381>Question 549381</A>: <I><SPAN STYLE=\"word-break: break-all;\"> under what conditions it has been following matrix equality?\r<BR>\n" );
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document.write( "( x y)  *  (1 1)    =   (1 1)  *  (x y)<BR>\n" );
document.write( "( z w)     (0 1)   ....     (0 1)     (z w)\r<BR>\n" );
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document.write( "Answer: provided that z = 0 and x = w\r<BR>\n" );
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document.write( "How? Thank you </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #357703 by </B><A HREF=/tutors/aboutme.mpl?userid=stanbon><B>stanbon(75887)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=stanbon><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=357703\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> under what conditions it has been following matrix equality? <BR>\n" );
document.write( "( x y) * (1 1) = (1 1) * (x y)<BR>\n" );
document.write( "( z w) * (0 1) = (0 1) * (z w) <BR>\n" );
document.write( "Answer: provided that z = 0 and x = w <BR>\n" );
document.write( "How?<BR>\n" );
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document.write( "Equations:<BR>\n" );
document.write( "x + 0*y = x + z<BR>\n" );
document.write( "x +  y  = y + w<BR>\n" );
document.write( "z + 0*w = z + w<BR>\n" );
document.write( "z +  w = 0y + w<BR>\n" );
document.write( "--------------------<BR>\n" );
document.write( "From the 2nd row: x = w<BR>\n" );
document.write( "From the 4th row: z = 0\r<BR>\n" );
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document.write( "===============================<BR>\n" );
document.write( "Cheers,<BR>\n" );
document.write( "Stan H. </SPAN>\n" );
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