document.write( "Question 1093831: Daniel purchased a laptop for $1180 . Currently, 3 years later, the laptop is worth $805 .
\n" ); document.write( "Assuming that the value is changing linearly, estimate the value of the laptop 4 years from now (a total of 7 years after it was first bought). \n" ); document.write( "

Algebra.Com's Answer #708539 by josmiceli(19441) $\"\"$ $\"About$

You can put this solution on YOUR website!
Plot time in yrs on the horizontal axis
\n" ); document.write( "Plot value of the laptop on the vertical axis
\n" ); document.write( "Let $\"+x+=+0+\"$ be the time in yrs when he bought it
\n" ); document.write( "Use general point-slope formula
\n" ); document.write( " $\"+%28+805+-+1180+%29+%2F+%28+3+-+0+%29+=+%28+y+-+1180+%29+%2F+%28+x+-+0+%29+\"$
\n" ); document.write( " $\"+%28+-375+%29+%2F+3+=+%28+y+-+1180+%29+%2F+x+\"$
\n" ); document.write( " $\"+-375x+=+3y+-+3540+\"$
\n" ); document.write( " $\"+3y+=+-375x+%2B+3540+\"$
\n" ); document.write( " $\"+y+=+-125x+%2B+1180+\"$
\n" ); document.write( "--------------------------
\n" ); document.write( " $\"+x+=+7+\"$
\n" ); document.write( " $\"+y+=+-125%2A7+%2B+1180+\"$
\n" ); document.write( " $\"+y+=+-875+%2B+1180+\"$
\n" ); document.write( " $\"+y+=+305+\"$
\n" ); document.write( "It will be worth $305
\n" ); document.write( "------------------------
\n" ); document.write( "check:
\n" ); document.write( "Does equation go through ( 3, 805 ) ?
\n" ); document.write( " $\"+y+=+-125x+%2B+1180+\"$
\n" ); document.write( " $\"+805+=+-125%2A3+%2B+1180+\"$
\n" ); document.write( " $\"+805+=+-375+%2B+1180+\"$
\n" ); document.write( " $\"+805+=+805+\"$
\n" ); document.write( "OK
\n" ); document.write( " \n" ); document.write( "

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