Question 123050
Suppose you buy flour and cornmeal in bulk to make flour tortillas and corn tortillas.
Flour costs $1.50/lb.Cornmeal costs $2.50/lb.
You want to spend less than $9.50 on flour and cornmeal,and you need at least 4 lb altogether.
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a.Write a system of inequalities that describes this situation.
0<=f<=4
0<=c<=0
Quantity Inequality: f+c>=4
Cost Inequality: 1.5f + 2.5c <9.5
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b.Graph the system to show all possible solutions.
Draw a vertical line at c=4
Draw a horizontal line at f=4
Graph f=4-c as a solid line.
Shade the half-plane above it.
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Graph f=(-2.5/1.5)c+(9.5/1.5) as a dashed line.
Shade the half-plane below it.
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The intersection of the half-planes including the boundary f=4-c
is the solution area.
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Cheers,
Stan H.
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{{{graph(400,300,-10,10,-10,10,4-x,(-2.5/1.5)x+(9.5/1.5))}}}
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Cheers,
stan H.