Question 5 • Mathematics III
Revenue from selling x vacuum cleaners is y = 280x. The cost function has vertex (500, 24,000), so it can be written as y = a(x − 500)² + 24,000. Using the y-intercept (0, 11,000) gives 11,000 = 250,000a + 24,000, so a = −0.052. Thus choice C gives the revenue and cost equations whose intersection identifies the break-even sales amounts.
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