Question 65645
A small firm produces both AM and AM/FM car radios. 
The AM radios take 15 h to produce, and the AM/FM radios take 20 h. 
The number of production hours is limited to 300 h per week. 
The plant’s capacity is limited to a total of 18 radios per week, and existing orders require that at least 4AM radios and at least 3 AM/FM radios be produced per week. 
Write a system of inequalities representing this situation. 
Then, draw a graph of the feasible region given these conditions, in, which x is the number of AM radios and y the number of AM/FM radios. 
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Let number of AM radios be "a": Hours to produce = 15a hours
Let number of FM radios be "f": Hours to produce is 20f hours
a+f<=18
4<=a<=18
3<=f<=18
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Solve for f: f<=-a+18
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Graph the equality and the half-plane below it.
Draw vertical lines at a=4 and a=18
Draw horizontal lines at f=3 and f=18
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{{{graph(600,400,-5,25,-5,25,-x+18)}}}
Cheers,
Stan H.