HTML to PHP echo error

Im still new in PHP, HTML or Javascipt. Im trying to find solution about this problem.

I got this error

Parse error: syntax error, unexpected T_ENCAPSED_AND_WHITESPACE, expecting T_STRING or T_VARIABLE or T_NUM_STRING when trying to show in echo.

Original Code

" />

when change to echo

echo "\" />\n";

Can someone help me or explain why?

Thank you..