Answer:
a=1, b=2, c=5, d=1, e=6
Step-by-step explanation:

So 
First you have to multiply -8 to (-4x-1)
which is, -12x+8
then there is -9x you have to add like terms
-12x-9x+8
-21x+8 is your final answer
Answer:
Tn = 64-4n
Step-by-step explanation:
The nth term of an AP is expressed as:
Tn = a+(n-1)d
a is the common difference
n is the number of terms
d is the common difference
Given the 6th term a6 = 40
T6 = a+(6-1)d
T6 = a+5d
40 = a+5d ... (1)
Given the 20th term a20 = -16
T20 = a+(20-1)d
T20 = a+19d
-16 = a+19d... (2)
Solving both equation simultaneously
40 = a+5d
-16 = a+19d
Subtracting both equation
40-(-16) = 5d-19d
56 = -14d
d = 56/-14
d = -4
Substituting d = -4 into equation
a+5d = 40
a+5(-4) = 40
a-20 = 40
a = 20+40
a = 60
Given a = 60, d = -4, to get the nth term of the sequence:
Tn = a+(n-1)d
Tn = 60+(n-1)(-4)
Tn = 60+(-4n+4)
Tn = 60-4n+4
Tn = 64-4n
We have
1G = 12.05 - 3D;
Then,
2D + 3( 12.05 - 3D) = 15.50;
2D + 36.15 - 9D = 15.50;
- 7D = - 20.65;
D = 2.95;
Finally, G = 12.05 - 3 x 2.95;
G = 3.20;
A googol is bigger than a billion.