Answer:

Step-by-step explanation:
Combining like-terms gives us 
Hope this helped!
Q = 21
29 - q = 8
First subtract 29 from both sides.
-q = 8 - 29
Subtract 29 from 8 which is -21.
Then flip the signs.
q = 21
It's hard to explain, but theres a trick to it too.
Rate of change
find a2 and a4
a2=27(1/3)^(2-1)=27 times 1/3=9
a4=27(1/3)^(4-1)=27 times 1/27=1
rate of change=(a4-a2)/(4-2)=(1-9)/(4-2)=-8/2=-4
average rate of change is -4