document.write( "Question 1145901: 15 articles are bought.some cost 5 c each and the remainder cost 8 c each. if the total amount spent is 90 c, how many of each are bought? \n" ); document.write( "

Algebra.Com's Answer #767170 by VFBundy(438) $\"\"$ $\"About$

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5 cent items = x
\n" ); document.write( "8 cent items = y
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\n" ); document.write( "Make two equations:
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\n" ); document.write( "x + y = 15
\n" ); document.write( "5x + 8y = 90
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\n" ); document.write( "Multiply the first equation by -8:
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\n" ); document.write( "-8x - 8y = -120
\n" ); document.write( "5x + 8y = 90
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\n" ); document.write( "Add both equations together, then solve for x:
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\n" ); document.write( "-3x = -30
\n" ); document.write( "x = 10
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\n" ); document.write( "Now that we know x = 10, substitute this into either one of the original two equations, then solve for y:
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\n" ); document.write( "x + y = 15
\n" ); document.write( "10 + y = 15
\n" ); document.write( "y = 5
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\n" ); document.write( "5 cent items = x = 10
\n" ); document.write( "8 cent items = y = 5 \n" ); document.write( "

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