Cubic Function?

Question

Write an equation that can be used to solve the following problem: The cubic function C(t) = 1.054t3 + 28.0729t2 + 238.50t + 1122.6 can be used to model carbon emission in millions of metric tons from consumption of solid fuels (e.g. coal and wood) in the U.S. in the year 2000 + t. According to the model, in which year(s) will (or was) carbon emission from the consumption of solid fuels equal to 900 million metric tons.

I put:
900 = 1.054(t)^3+28.0729(t)^2+238.50(t)+1122.6

But it was marked wrong. Where did I go wrong?

Answer 1

From what I see, the question asks for the year C(t) = 900 million tons
You needed to solve for t then it should be added to 2000 to get the sought answer.

What you did wasn't wrong, just incomplete.

the next step would have been to factor out a t and end up with a quadratic, t and a quantity.

Answer 2

I think that your equation is on the right track, but the other part of the question asks in which year(s) will (or was) the emission from solid fuels equal to 900. This would be t=0 or the year 2000, in which, according to the model, emissions were 1122.6

C(0) = 1122.6