Slopt in form ax+by=c is -a/b
-3/3=-1
slope is -1
intercept in form ax+by=c is c/b
63/3=9
slope is -1
intercept is at y=9
Answer:
-14.2, -7.8, 12.6, 15.3
Step-by-step explanation:
A perfect square must be hidden within all of those radicands in order to simplify them down to what the answer is.

.

.

. The rules for adding radicals is that the index has to be the same (all of our indexes are 2 since we have square roots), and the radicands have to be the same. In other words, we cannot add the square root of 4 to the square root of 5. They either both have to be 4 or they both have to be 5. So here's what we have thus far:

. We can add

and

to get

. That means as far as our answer goes, A = 72 and B = 4, or (72, 4), choice a.
Assuming by "20111" you mean 2011.
The difference in years is 2011 and 1990 is 21 years.
In 21 years the rate of change was "-$1850" (44,450 - 6,300).
Furthermore, this can be divided by 21 to get the AVERAGE rate of change in 1 year
21 years / -1850 = -$88.096 (3 DP)