document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=1181725>Question 1181725</A>: <I><SPAN STYLE=\"word-break: break-all;\"> The safe stopping distance, d, in metres, for a boat travelling at v km/h in calm water is determined to be d = 0.002 (2v^2 + 10v + 3000) .<BR>\n" );
document.write( "a) What is the safe stopping distance if the speed is 12 km/h?<BR>\n" );
document.write( "b) What is the initial speed of the boat if it takes 15 m to stop? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #811703 by </B><A HREF=/tutors/aboutme.mpl?userid=Boreal><B>Boreal(15235)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=Boreal><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=Boreal><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=811703\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> if speed is 12 km/h<BR>\n" );
document.write( "=0.002[2*12^2+10(12)+3000)]<BR>\n" );
document.write( "=6.528 m<BR>\n" );
document.write( "-<BR>\n" );
document.write( "15=.002(2v^2+10v+3000)=0.004v^2+0.02v+6<BR>\n" );
document.write( "so 0.004v^2+0.02c-9=0<BR>\n" );
document.write( "4v^2+20v-9000=0<BR>\n" );
document.write( "v^2+5v-2250=0<BR>\n" );
document.write( "(v+50)(v-45)=0<BR>\n" );
document.write( "v=45 km/h </SPAN>\n" );
document.write( "</TD></TR></TABLE>\n" );