document.write( "Question 473103: Hello I need help setting up the equation for this word problem. \r
\n" ); document.write( "\n" ); document.write( "The monthly revenue achieved by selling x wristwatches is x(40-o.2x)dollars. The cost of each watch is $28. Howw many watched must be sold each month to acheive a profit (revenue minus cost) of at leaast $100? Must set up an algebraic inequality and solve it. \r
\n" ); document.write( "\n" ); document.write( "Thank you! \n" ); document.write( "
Algebra.Com's Answer #324459 by ankor@dixie-net.com(22740)\"\" \"About 
You can put this solution on YOUR website!
The monthly revenue achieved by selling x wristwatches is x(40-0.2x)dollars.
\n" ); document.write( " The cost of each watch is $28.
\n" ); document.write( "How many watches must be sold each month to acheive a profit (revenue minus cost) of at leaast $100?
\n" ); document.write( " Must set up an algebraic inequality and solve it.
\n" ); document.write( ":
\n" ); document.write( "Cost = 28x
\n" ); document.write( ":
\n" ); document.write( "Rev - cost = at least $100
\n" ); document.write( "x(40-.2x) - 28x => 100
\n" ); document.write( "40x - .2x^2 - 28x => 100
\n" ); document.write( "-.2x^2 + 12x - 100 => 0
\n" ); document.write( "multiply by -5, to make easier to factor
\n" ); document.write( "x^2 - 60x + 500 => 0
\n" ); document.write( "factors to:
\n" ); document.write( "x = 50
\n" ); document.write( "x => 10
\n" ); document.write( ":
\n" ); document.write( "We can say at least sell 10 watches to make at least $100 \n" ); document.write( "
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