document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=523286>Question 523286</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The function f is linear and satisfies f(d+1)-f(d)=3 for all real numbers d.  What is  f(3)-f(5)?  Please show your work.\r<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 #347390 by </B><A HREF=/tutors/aboutme.mpl?userid=richard1234><B>richard1234(7193)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=richard1234><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=richard1234><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=347390\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> The equation \"f(d+1) - f(d) = 3\" already implies that the slope of f is 3, since we know the function is linear. Hence we can write f(x) = 3x + b for some real number b. Then f(3) - f(5) = (9+b) - (15+b) = -6. </SPAN>\n" );
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