linear equations and problem solving , multiple choice help

linear equations and problem solving , multiple choice help

Find the values of x and y in the following isosceles triangle.

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x = 47.5, y = 66.25

x = 0, y = 190

x = 5, y = 175

x = 40, y = 70

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How many units of x must be sold to break even if the cost function is C(x) = 0.8x + 900 and the revenue function is R(x) = 2x? Round to the nearest unit, if necessary.

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432 units

321 units

750 units

450 units

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The planning department of Abstract Office Supplies has been asked to determine whether the company should introduce a new computer desk next year. The department estimates that $6000 of new manufacturing equipment will need to be purchased and that the cost of constructing each desk will be $200. The department also estimates that the revenue from each desk will be $450.

Which cost function C(x) and revenue function R(x) can be used to model this scenario?

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