select the correct answer. an entrepreneur estimates his total profit (total revenue minus total cost) for…

select the correct answer. an entrepreneur estimates his total profit (total revenue minus total cost) for his proposed company as $p(x)=x^{3}-4x^{2}+5x - 20$, where $p$ is in hundreds of dollars and $x$ is number of years the company has been in business. in which year ($x$) will the entrepreneur break even?\na. year 1\nb. year 2\nc. year 3\nd. year 4
Answer
Answer:
D. year 4
Explanation:
Step1: Define break - even condition
At break - even, $p(x)=0$, so we set $x^{3}-4x^{2}+5x - 20 = 0$.
Step2: Factor the polynomial
Group the terms: $(x^{3}-4x^{2})+(5x - 20)=0$. Then $x^{2}(x - 4)+5(x - 4)=0$, which factors to $(x - 4)(x^{2}+5)=0$.
Step3: Solve for x
Set each factor equal to zero. For $x^{2}+5 = 0$, $x^{2}=-5$, and the solutions are $x=\pm\sqrt{-5}$ (non - real). For $x - 4=0$, $x = 4$. So the entrepreneur breaks even in year 4.