document.write( "Question 158951: Justin has already saved $100 and wants to buy a playstation 2 for $129 about four weeks from now. To find how much he should save each week between now and then, he wrote 100+4x=139.99. Explain this equation \n" ); document.write( "

Algebra.Com's Answer #117216 by Fombitz(32388) $\"\"$ $\"About$

You can put this solution on YOUR website!
I think you meant to write
\n" ); document.write( " $\"100%2B4x=129\"$
\n" ); document.write( "He's saving money to buy the PS2 for $129.
\n" ); document.write( "He starts out with $100.
\n" ); document.write( "The first week he saves, x, so his total is 100+x.
\n" ); document.write( "The second week he saves another x, so his total is (100+x)+x or 100+2x.
\n" ); document.write( "I think you see the pattern here.
\n" ); document.write( "Third week, (100+2x)+x or 100+3x.
\n" ); document.write( "After 4 weeks he will have 100+4x.
\n" ); document.write( "His goal is $129.
\n" ); document.write( "Set those two equal to each to find out what x should be.
\n" ); document.write( " $\"100%2B4x=129\"$
\n" ); document.write( " $\"4x=29\"$
\n" ); document.write( " $\"x=29%2F4\"$
\n" ); document.write( "x=$7.25
\n" ); document.write( "He needs to save $7.25 per week to buy the PS2. \n" ); document.write( "

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