document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=136740>Question 136740</A>: <I><SPAN STYLE=\"word-break: break-all;\"> Hi, <BR>\n" );
document.write( "    Can you help me with this math problem?\r<BR>\n" );
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document.write( "Solve the problem.<BR>\n" );
document.write( "15.) The sum of the squares of the digits of a positive two-digit number is 20, and the tens digit is 2 more than the units digit. Find the number. \r<BR>\n" );
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document.write( "The answer should be 42 </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #100105 by </B><A HREF=/tutors/aboutme.mpl?userid=solver91311><B>solver91311(24713)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=solver91311><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=solver91311><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=100105\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> If x is the 10s digit and y is the 1s digit, we know that <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x=y%2B2 ALIGN=MIDDLE  ALT=\"x=y%2B2\"   DISABLED_style= \"max-width:90%; height:auto;\" > and <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2By%5E2=20 ALIGN=MIDDLE  ALT=\"x%5E2%2By%5E2=20\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "First, substitute <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=y%2B2 ALIGN=MIDDLE  ALT=\"y%2B2\"   DISABLED_style= \"max-width:90%; height:auto;\" > for <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x ALIGN=MIDDLE  ALT=\"x\"   DISABLED_style= \"max-width:90%; height:auto;\" > in <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=x%5E2%2By%5E2=20 ALIGN=MIDDLE  ALT=\"x%5E2%2By%5E2=20\"   DISABLED_style= \"max-width:90%; height:auto;\" >:\r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28y%2B2%29%5E2%2By%5E2=20 ALIGN=MIDDLE  ALT=\"%28y%2B2%29%5E2%2By%5E2=20\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "Now, expand the binomial, collect like terms, move the constant term to the left side setting the entire expression equal to zero.  That gives you a quadratic that you can solve by factoring.  Exclude the negative root because it is extraneous introduced by the act of squaring the variable.  The other root will be the value of the 1s digit and you can easily calculate the 10s digit given that information. </SPAN>\n" );
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