Answer:
<h2>M(-a, b)</h2>
Step-by-step explanation:
Use the formula of a midpoint:

We have the points P(-2a, 0) and Q(0, 2b). Substitute:

Find the slope between the 2 points and plug inotllto point slope form
Answer:
A) R = 1900 -24t
B) 1684 billion barrels
C) 79.17 years
Step-by-step explanation:
<h3>A)</h3>
Reserves start at 1900 billion barrels and decrease by 24 billion barrels each year. The value for t=0 is 1900; the value for t=1 is 24 less.
R = 1900 -24t
__
<h3>B)</h3>
For t=9, the reserves will be ...
R = 1900 -24(9) = 1900 -216 = 1684 . . . . billion barrels
__
<h3>C)</h3>
The reserve will be 0 when ...
0 = 1900 -24t
24t = 1900 . . . . . add 24t
t ≈ 79.17 . . . . divide by 24
Reserves will be gone in about 79.17 years.
3 is a negative so it 3,604