The polynomial 0.0011x^3 - 0.07x^2 + 1.7x + 13 models natural gas consumption in trillions of cubic feet, where x equals = 0 corresponds to 1960, x equals = 1 to 1961, and so on.
In which year between 1970 and 1990 was natural gas consumption about 25.7 trillion cubic feet?
OMG I hate this crap. Not really I just hate that it makes me feel like an idiot. Any advice?
Cant I just rewrite it like so?
0.0011x^3 - 0.07x^2 + 1.7x + 13 - 25.7 = Year
In this case Year = 1960 + x , so the year 1970 means x =10 and 1990 gives x = 30.
What the equation gives is the number of cubic gas used in a year (not the year itself), so if you feed in the numbers 10 to 30 as x, and see what values you get it will tell you which year's consumption is closest to 25,700,000,000,000.
Oh yeah duh OMG see this metal abuse it does to me. So I just test numbers between 10-30 until I hit the 25.7 trillion cubic feet. Thanks.