Question 411817
 Brand x cost $25 per bag and contains 2 units of nutritional element A, 2 units of element B,
 and 2 units of element C.
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 Brand Y costs $20 per bag and contains 1 unit of nutritional A, 9 units of B and 3 units of C.
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 Find the number of bags of each brand that should be mixed to provide a mixture having a minimum cost per bag.
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Requirements of nutrients A: 12 B:36 C:24 units.
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Let x = no. of bags of x
Let y = no. of bags of y
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Write an equation for each element, put in the slope/intercept for graphing
element A equation
2x + 1y = 12
y = -2x + 12 (Red)
:
element B equation
2x + 9y = 36
9y = -2x + 36
y = {{{-2/9}}}x + 4; (green)
:
element C equation
2x + 3y = 24
3y = -2x + 24
y = {{{-2/3}}} + 8; (purple)
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Graph these three equations
{{{ graph( 300, 200, -6, 10, -10, 20, -2x+12, (-2/9)x+4, (-2/3)x+8 ) }}}
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I'm going to say 3 bags of x, and 6 bags of y