Answer:
The first choice is correct.
Step-by-step explanation:
First work out the common ratio r:-
a2 = a1r and a5 = a1 r^4
So r^3 = a1r^4 / a1r = 256/ 108
r = cube root (256/-108) = 4/3
So the explicit formula is 108(4/3)^(n-1)
Answer:

Step-by-step explanation:
You add the exponents when the number/variable is the same, so:
6+8+n= 14+n
So:

Let, the height of a tree = x
Then, x/16 = 5 1/4 / 4
x/16 = 21 / 4*4
x/16 = 21/16
x = 21
In short, Height of the Tree is 21 Feet
Hope this helps!
Answer: c = 520
Step-by-step explanation:
f(2) = 578 means that when x = 2, the value is equal to 578. We will plug these knowns in and then solve for c.
Given:
f(x) = 4x³ + 7x² - x + c
Substitute:
578 = 4(2)³ + 7(2)² - (2) + c
Distribute:
578 = 4 * 2³ + 7 * 2² - 2 + c
Raise to the power of 3 and 2:
578 = 4 * 8 + 7 * 4 - 2 + c
Multiply:
578 = 32 + 28 - 2 + c
Add:
578 = 60 - 2 + c
Subtract:
578 = 58 + c
Subtract 58 from both sides:
520 = c
Reflexive property:
c = 520
Hello,
I have search in my memory : (not sure)

But we can make easier (see picture)