document.write( "Question 640035: Suppose you have a budget of 400 dollars for one month. You would like to buy some textbooks and CDs.
\n" ); document.write( "The average cost of a book is 55 dollars each and that of a CD is
\n" ); document.write( "13 dollars each. Let x denote the number of books you buy and y denote the
\n" ); document.write( "number of CDs that you buy. Write the equation of your budget constraint in the form y=mx+b, where m and b are some numbers.
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Algebra.Com's Answer #403001 by solver91311(24713) $\"\"$ $\"About$

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\n" ); document.write( "\n" ); document.write( "Constraints are inequalities, not equations. Furthermore, given the cost data provided and the fact that you can't buy fractional parts of either CDs or books, there is no combination of $13 items and $55 items that total $400 -- which is simply more evidence that this should be an inequality rather than an equation.\r
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\n" ); document.write( "\n" ); document.write( "What would have been appropriate is to ask you to write the equation, in slope-intercept form, that represents the boundary line of the budget constraint inequality solution set half-plane. Such an equation would have the form

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\n" ); document.write( "\n" ); document.write( "If

represents the number of books purchased, then the total cost of those $55 books is

. Likewise the total cost of the CDs purchased is

.\r
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\n" ); document.write( "\n" ); document.write( "Then, since the budget is $400, meaning that you cannot spend MORE than $400, but you can always spend LESS, the constraint inequality is:\r
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\r
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\n" ); document.write( "\n" ); document.write( "An equation of the boundary line of the constraint inequality is found by replacing the inequality sign with an equals sign.\r
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\r
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\n" ); document.write( "\n" ); document.write( "Then add

to both sides and multiply both sides by

to put the equation into slope-intercept form.\r
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\n" ); document.write( "\n" ); document.write( "John
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\n" ); document.write( "My calculator said it, I believe it, that settles it
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$\"The$

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