document.write( "Question 52092This question is from textbook PH Alg-1
\n" ); document.write( ": I am thrown by this one. I have no total to work with and I should read it some other way. Please help.
\n" ); document.write( "This is how I started.\r
\n" ); document.write( "\n" ); document.write( "placing planks of equal length end to end, J found that 3 planks were one foot too short and 4 planks were two feet too long. Find the length of the planks\r
\n" ); document.write( "\n" ); document.write( "I did: X+3(X-1)+4(X-2)
\n" ); document.write( "where am I wrong? \n" ); document.write( "
Algebra.Com's Answer #34738 by Earlsdon(6294)\"\" \"About 
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Try this:
\n" ); document.write( "Let x = the length required to be covered and L = the length of a plank.
\n" ); document.write( "1) 3L = x-1 Multiply this by 4.
\n" ); document.write( "2) 4L = x+2 Multiply this by 3.\r
\n" ); document.write( "\n" ); document.write( "1a) 12L = 4x-4
\n" ); document.write( "2a) 12L = 3x+6 Subtract equation 2a) from 1a)
\n" ); document.write( "3) 0 = x-10 Add 10 to both sides.
\n" ); document.write( "x = 10 Substitute this into equations 1) and 2) and solve for L\r
\n" ); document.write( "\n" ); document.write( "3L = 10 - 1 = 9: L = 3
\n" ); document.write( "4L = 10 + 2 = 12: L = 3\r
\n" ); document.write( "\n" ); document.write( "The planks are 3 feet long.\r
\n" ); document.write( "\n" ); document.write( "Check:
\n" ); document.write( "3L = 9 = 10-1
\n" ); document.write( "4L = 12= 10+2 \n" ); document.write( "
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