document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1072495>Question 1072495</A>: <I><SPAN STYLE=\"word-break: break-all;\"> describe the relationship between the graph of y=2x +1 and it's reflection across the line y=x<BR>\n" );
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document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #687385 by </B><A HREF=/tutors/aboutme.mpl?userid=math_helper><B>math_helper(2461)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=math_helper><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=math_helper><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=687385\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> describe the relationship between the graph of y=2x +1 and it's reflection across the line y=x<BR>\n" );
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document.write( "The reflected line will have the equation (using capital X & Y to differentiate this as the reflected line:  <BR>\n" );
document.write( " <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+Y+=+%281%2F2%29X+-+1%2F2+ ALIGN=MIDDLE  ALT=\"+Y+=+%281%2F2%29X+-+1%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  which can be found as follows:\r<BR>\n" );
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document.write( "Start with  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+y+=+2x%2B1+ ALIGN=MIDDLE  ALT=\"+y+=+2x%2B1+\"   DISABLED_style= \"max-width:90%; height:auto;\" > and solve for x:   <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+x+=+%28y+-+1%29%2F2++=+%281%2F2%29y+-+1%2F2+ ALIGN=MIDDLE  ALT=\"+x+=+%28y+-+1%29%2F2++=+%281%2F2%29y+-+1%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >.   Then replace y with X and x with Y to get  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+Y+=+%281%2F2%29X+-+1%2F2+ ALIGN=MIDDLE  ALT=\"+Y+=+%281%2F2%29X+-+1%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >\r<BR>\n" );
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document.write( "For every (a,b) on y=2x+1,  if you project horizontally to y=x then vertically to Y=(1/2)X-1/2 you will find it meets the reflection at  X=b, and Y=a.\r<BR>\n" );
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document.write( "Black line:  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++y=2x+%2B1+ ALIGN=MIDDLE  ALT=\"++y=2x+%2B1+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Green line:  <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=++Y+=+%281%2F2%29X+-+1%2F2+ ALIGN=MIDDLE  ALT=\"++Y+=+%281%2F2%29X+-+1%2F2+\"   DISABLED_style= \"max-width:90%; height:auto;\" >  <BR>\n" );
document.write( "Red line: <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+y=x+ ALIGN=MIDDLE  ALT=\"+y=x+\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "The two lines intersect at (-1,-1) \r<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=+drawing%28+300%2C+300%2C+-5%2C+5%2C+-5%2C+5%2C%0D%0A++grid%28+1+%29%2C%0D%0A++line%28+-2.5%2C+-4%2C+1.5%2C+4+%29%2C%0D%0A++green%28line%28-4%2C-2.5%2C4%2C1.5%29%29%2C%0D%0A++red%28line%28-4%2C-4%2C+4%2C4%29%29%0D%0A%29%0D%0A ALIGN=MIDDLE   DISABLED_style= \"max-width:90%; height:auto;\" > </SPAN>\n" );
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