Question 673212
Suppose the cost to produce 10 units of a product is $20 and the cost to produce 20 units is $70. Find the equation of the line, then find the cost to produce 35 units. 
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You have 2 points:: (10,20) and (20,70)
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slope = (70-20)/(20-10) = 50/10 = 5
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Form:: y = mx + b
Solve for "b":
20 = 5*10 + b 
b = -30
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Equation:
y = 5x - 30
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Cheers,
Stan H.
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