document.write( "Question 757552: The cost of three notebooks and four pencils is $8.50. The cost of five notebooks and eight pencils is $14.50. Determine the cost of one notebook and the cost of one pencil. \n" ); document.write( "

Algebra.Com's Answer #460893 by Cromlix(4381) $\"\"$ $\"About$

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Notebook = x
\n" ); document.write( "Pencil = y
\n" ); document.write( "3x + 4y = 8.50........1
\n" ); document.write( "5x + 8y = 14.50.......2
\n" ); document.write( "Multiply (1) by 2
\n" ); document.write( "6x + 8y = 17.00.......3
\n" ); document.write( "5x + 8y = 14.50.......2
\n" ); document.write( "Subtract (2) from (3)
\n" ); document.write( " x = 2.50
\n" ); document.write( "Substitute x = 2.50 in Eq(1)
\n" ); document.write( " 3x + 4y = 8.50
\n" ); document.write( "7.50 + 4y = 8.50
\n" ); document.write( " 4y = 8.50 - 7.50
\n" ); document.write( " 4y = 1.00
\n" ); document.write( " y = 0.25
\n" ); document.write( "Notebook costs $2.50
\n" ); document.write( "Pencil costs $0.25
\n" ); document.write( "Hope this helps.
\n" ); document.write( ":-) \n" ); document.write( "

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