document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1109263>Question 1109263</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The number of streetlights in a town is growing linearly.  Four months ago (n = 0) there were 130 lights.  Now (n = 4) there are 146 lights.  If this trend continues,\r<BR>\n" );
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document.write( "-Find an explicit formula for the number of lights in month n\r<BR>\n" );
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document.write( "-How many months will it take to reach 200 lights?\r<BR>\n" );
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document.write( "I think the difference is 4 therefore, the equation thus far is, p_(n)=p_(o)+4n.<BR>\n" );
document.write( "Is P_(o) 130 since that is the starting amount? If so, then I can just substitute 200 for p_(n) to solve for the second question.  </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #724252 by </B><A HREF=/tutors/aboutme.mpl?userid=rothauserc><B>rothauserc(4718)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=rothauserc><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=rothauserc><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=724252\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> (146 - 130) / 4 = 4, so 4 lights are added each month<BR>\n" );
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document.write( "let y be the total number of lights for a given month<BR>\n" );
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document.write( "y = 4n + 130<BR>\n" );
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document.write( "200 = 4n + 130<BR>\n" );
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document.write( "4n = 70<BR>\n" );
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document.write( "n = 17.5 months<BR>\n" );
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document.write( "your formula is correct<BR>\n" );
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