SOLUTION: I would love help solving this polynomial question. The polynomial function I (t) = -0.1T^2+2T represent the yearly income or loss from a real estate investment, where t is time

Algebra ->  Polynomials-and-rational-expressions -> SOLUTION: I would love help solving this polynomial question. The polynomial function I (t) = -0.1T^2+2T represent the yearly income or loss from a real estate investment, where t is time      Log On


   

Question 363575: I would love help solving this polynomial question.
The polynomial function I (t) = -0.1T^2+2T represent the yearly income or loss from a real estate investment, where t is time in years. After how many years does income begin to decline? Round to the nearest tenth of a year if neccessary.

Answer by ewatrrr(24785) About Me  (Show Source):
You can put this solution on YOUR website!


Hi, 

Re:  Annual Income = I(t) = -0.1t^2+2t where t is time in years

I(t) = -.1t(t - 20)

I(0) = 0 & I(20) = O



I(t) = -0.1t^2+2t  (note: negative coefficient of the squared term)

graph of this parabola opens downward, with a maximum at 10years (0+20)/2 

After 10 years, the income begins to decline. 

graph%28+300%2C+300%2C-0%2C25%2C-25%2C25%2C-.1x%5E2+%2B+2x%2B0%29