document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1184544>Question 1184544</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Abu came out of the bakery shop after spending RM 320 on carrot cakes, cheese cakes<BR>\n" );
document.write( "and chocolate cakes for his school’s Canteen Day. Altogether, he bought 21 cakes. The<BR>\n" );
document.write( "prices for each carrot cake, cheese cake and chocolate cake are RM 10, RM 20 and RM<BR>\n" );
document.write( "15 respectively. The number of chocolate cakes bought was twice the total number of<BR>\n" );
document.write( "carrot and cheese cakes. By using inverse matrix method, find how many each type of<BR>\n" );
document.write( "cakes that Abu has bought. </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #815242 by </B><A HREF=/tutors/aboutme.mpl?userid=robertb><B>robertb(5830)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=robertb><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/cgi-bin/show-face.mpl?user=robertb><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=815242\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> Let x =  # of carrot cakes, y = # of cheese cakes, and z = # of chocolate cakes.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "===> The system is <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28matrix%283%2C1%2C+x%2By%2Bz+=+21%2C+10x%2B20y%2B15z+=+320%2C+z+=+2x%2B2y%29%29 ALIGN=MIDDLE  ALT=\"system%28matrix%283%2C1%2C+x%2By%2Bz+=+21%2C+10x%2B20y%2B15z+=+320%2C+z+=+2x%2B2y%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=system%28matrix%283%2C1%2C+x%2By%2Bz+=+21%2C+2x%2B4y%2B3z+=+64%2C+2x%2B2y-z=0%29%29 ALIGN=MIDDLE  ALT=\"system%28matrix%283%2C1%2C+x%2By%2Bz+=+21%2C+2x%2B4y%2B3z+=+64%2C+2x%2B2y-z=0%29%29\"   DISABLED_style= \"max-width:90%; height:auto;\" >, or   <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28matrix%283%2C3%2C+1%2C1%2C1%2C2%2C4%2C3%2C2%2C2%2C-1%29%29%2A%28matrix%283%2C1%2Cx%2Cy%2Cz%29%29+=+%28matrix%283%2C1%2C+21%2C64%2C0%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >  equivalently.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "===> <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28matrix%283%2C1%2Cx%2Cy%2Cz%29%29+=+%28matrix%283%2C3%2C+1%2C1%2C1%2C2%2C4%2C3%2C2%2C2%2C-1%29%29%5E%28-1%29%2A%28matrix%283%2C1%2C+21%2C64%2C0%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "I now refer you to https://www.emathhelp.net/calculators/linear-algebra/inverse-of-matrix-calculator/, <BR>\n" );
document.write( "where the inverse of the above matrix can be calculated with all steps shown.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "===>  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28matrix%283%2C1%2Cx%2Cy%2Cz%29%29+=+%28matrix%283%2C3%2C+1%2C1%2C1%2C2%2C4%2C3%2C2%2C2%2C-1%29%29%5E%28-1%29%2A%28matrix%283%2C1%2C+21%2C64%2C0%29%29+=+%28matrix%283%2C3%2C5%2F3%2C-1%2F2%2C1%2F6%2C+-4%2F3%2C+1%2F2%2C+1%2F6%2C+2%2F3%2C+0%2C+-1%2F3%29%29%2A%28matrix%283%2C1%2C+21%2C64%2C0%29%29+=+%28matrix%283%2C1%2C+3%2C4%2C14%29%29 ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" >.\r<BR>\n" );
document.write( "<BR>\n" );
document.write( "\n" );
document.write( "The number of each type of cake bought is now clear.<BR>\n" );
document.write( " </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );