They are essentially asking us to solve:

Solving this equation for x tells us that it will take around 80.1 years for the materials in the vault to reduce to 357 pounds.
Answer:
Step-by-step explanation:
<u>Given function</u>
<u>To find</u>
<u>Solution</u>
Substitute x with 3 in the equation to find f(3)
- f(3) = -4(3+3) = -4*6 = -24
c square
its making me write 20 more characters
ignore this
the answer is c squared
I’m not sure I only answer these for the points :)