document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=300886>Question 300886</A>: <I><SPAN STYLE=\"word-break: break-all;\"> In Mr. Seeley's physics class, you have to find the total resistance (R) of a circuit with 2 resistors (r1 and r2 ) using the formuula R = r1r2 divided by r1 + r2.  r1 and r2 are the resistance of each resistor.  Resistance is measured in ohms.  A circuit thtat has a total resistance of 6 ohms has a 10-ohm resistor and an unknown resistor.  Find the resistance of the unknown resistor.    Please explain... I don't know where to begin this problem!!! </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #215957 by </B><A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><B>ankor@dixie-net.com(22740)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=ankor@dixie-net.com><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=ankor@dixie-net.com><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=215957\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> In Mr. Seeley's physics class, you have to find the total resistance (R) of a circuit with 2 resistors (r1 and r2 ) using the formula R = r1r2 divided by r1 + r2. r1 and r2 are the resistance of each resistor. Resistance is measured in ohms. A circuit that has a total resistance of 6 ohms has a 10-ohm resistor and an unknown resistor. Find the resistance of the unknown resistor. Please explain..<BR>\n" );
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document.write( "Begin by writing out the formula for 2 resistors in parallel<BR>\n" );
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document.write( "Rt = total resistance<BR>\n" );
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document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%28r1%2Ar2%29%2F%28r1%2Br2%29 ALIGN=MIDDLE  ALT=\"%28r1%2Ar2%29%2F%28r1%2Br2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = Rt<BR>\n" );
document.write( "In this problem<BR>\n" );
document.write( "r1 = 10<BR>\n" );
document.write( "r2 is unknown<BR>\n" );
document.write( "Rt = 6<BR>\n" );
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document.write( "Substituting<BR>\n" );
document.write( "<IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2810%2Ar2%29%2F%2810%2Br2%29 ALIGN=MIDDLE  ALT=\"%2810%2Ar2%29%2F%2810%2Br2%29\"   DISABLED_style= \"max-width:90%; height:auto;\" > = 6<BR>\n" );
document.write( "Multiply both sides by (10+r2), results<BR>\n" );
document.write( "10*r2 = 6(10 + r2)<BR>\n" );
document.write( "10*r2 = 60 + 6*r2<BR>\n" );
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document.write( "Subtract 6r2 from both sides<BR>\n" );
document.write( "10*r2 - 6*r2 = 60<BR>\n" );
document.write( "4*r2 = 60<BR>\n" );
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document.write( "divide both sides by 4<BR>\n" );
document.write( "r2 = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=60%2F4 ALIGN=MIDDLE  ALT=\"60%2F4\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "r2 = 15 ohms<BR>\n" );
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document.write( "Check solution in the formula<BR>\n" );
document.write( "Rt = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=%2810%2A15%29%2F%2810%2B15%29 ALIGN=MIDDLE  ALT=\"%2810%2A15%29%2F%2810%2B15%29\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "Rt = <IMG STYLE=\"max-width:80%;\" SRC=/cgi-bin/plot-formula.mpl?expression=150%2F25 ALIGN=MIDDLE  ALT=\"150%2F25\"   DISABLED_style= \"max-width:90%; height:auto;\" ><BR>\n" );
document.write( "R5 = 6  </SPAN>\n" );
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