88% not sure but I think so if it’s not the answer I’m sorry.
Answer:

Step-by-step explanation:
In order to write the series using the summation notation, first we need to find the nth term of the sequence formed. The sequence generated by the series is an arithmetic sequence as shown;
4, 8, 12, 16, 20...80
The nth term of an arithmetic sequence is expressed as Tn = a +(n-1)d
a is the first term = 4
d is the common difference = 21-8 = 8-4 = 4
n is the number of terms
On substituting, Tn = 4+(n-1)4
Tn = 4+4n-4
Tn = 4n
The nth term of the series is 4n.
Since the last term is 80, L = 4n
80 = 4n
n = 80/4
n = 20
This shows that the total number of terms in the sequence is 20
According to the series given 4 + 8 + 12 + 16 + 20+ . . . + 80
, we are to take the sum of the first 20terms of the sequence. Using summation notation;
4 + 8 + 12 + 16 + 20+ . . . + 80 = 
Answer:

Step-by-step explanation:
The given function is f(x)=x.
If we stretch vertically by a factor of 4 and a translation of 4 units up then the new function becomes

But f(x)=x
We substitute to obtain the equation of g(x) as

Answer:
g(3) = 17
Step-by-step explanation:
Step 1: Define
g(x) = 5x + 2
g(3) = x = 3
Step 2: Substitute and Evaluate
g(3) = 5(3) + 2
g(3) = 15 + 2
g(3) = 17
Big/small=4/7
r1/r2=4/7 where r1, r2 are radius of a big and small circles respectively
r1/3=4/7
r1=12/7
circumference of a big circle is2πr1=2π*12/7=24π/7 cm