document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1143327>Question 1143327</A>: <I><SPAN STYLE=\"word-break: break-all;\"> John is doing a push-up challenge. On day one he does three pushups. Each day after the first John will do 10 push-ups per day. Write a function p(d) for the number of pushups John will do on day d.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #764121 by </B><A HREF=/tutors/aboutme.mpl?userid=Theo><B>Theo(13342)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Theo><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=Theo><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=764121\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> on day 1, he does 3 pushups.<BR>\n" );
document.write( "on every day after day 1, he does 10 pushups.<BR>\n" );
document.write( "the general form of the linear equation for this is y = mx + b<BR>\n" );
document.write( "when x = 1, y = 3<BR>\n" );
document.write( "when x = 2, y = 13<BR>\n" );
document.write( "the slope of the equation is equal to m which is equal to (13 - 3) / (2 - 1) = 10 / 1 = 10<BR>\n" );
document.write( "the equation becomes y = 10x + b<BR>\n" );
document.write( "to find the value of b, use one of the points on the line.<BR>\n" );
document.write( "the point i used is the point equal to (1,3).<BR>\n" );
document.write( "the equation becomes 3 = 10 * 1 + b<BR>\n" );
document.write( "solve for b to get b = -7.<BR>\n" );
document.write( "the equation becomes y = 10x - 7.<BR>\n" );
document.write( "when x = 1, y = 3<BR>\n" );
document.write( "when x = 2, y = 13<BR>\n" );
document.write( "when x = 3, y = 23<BR>\n" );
document.write( "the  equation satisfies the requirements when x represents the number of days that the pushups are done.\r<BR>\n" );
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document.write( "you could also look at this as an arithmetic progression problem.<BR>\n" );
document.write( "when viewed that way, you get<BR>\n" );
document.write( "A1 = 3<BR>\n" );
document.write( "An = 3 + (n-1) * d<BR>\n" );
document.write( "d = 10<BR>\n" );
document.write( "formula becomes An = 3 + (n-1) * d<BR>\n" );
document.write( "when n = 1, A1 = 3 + 0 * 10 = 3<BR>\n" );
document.write( "when n = 2, A2 = 3 + 1 * 10 = 13<BR>\n" );
document.write( "when n = 3, A3 = 3 + 2 * 10 = 23<BR>\n" );
document.write( "etc.\r<BR>\n" );
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document.write( " </SPAN>\n" );
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