Answer:
A. R = -18t + 1,820
B. 1,568 billions of barrels
C. approximately 101.11 years
Step-by-step explanation:
To make our equation, we'll use the form R = mt + b. M represents how many billion barrels of oil are being lost each year, which we know is 18 billion. So -18 will be our m. B is how many total barrels of oil there are, which is 1,820. So 1,820 will be our b. Now the equation looks like this:
R = -18t + 1,820
We can use this equation to answer Part B.
Replace the t with 14:
R = -18(14) + 1,820
Now solve for R:
R = -18(14) + 1,820
R = -252 + 1,820
R = 1,568
14 years from now, there will be 1,568 billions of barrels left.
To solve part C, we need to find how many years it will take for all of the oil to be used up. After it's all used up, the total amount of oil will be 0, so we can replace R with 0 and then solve for t:
0 = -18t + 1,820
Subtract 1,820 from both sides to isolate -18t:
0 - 1,820 = -18t + 1,820 - 1,820
-1,820 = -18t
Divide both sides by -18 to isolate the t:
-1,820/-18 = -18t/-18
101.11 = t
After approximately 101.11 years, all of the oil will be used up.
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