Geometric sequence nth term:
tₙ = t₁ · (r)ⁿ⁻¹
t₁ = -2
t₄ = 128 (4th term)
formula for 4th term:
t₄ = -2 · (r)⁴⁻¹ = -2· (r)³
since t₄ = 128
128 = -2(r)³
(r)³ = -64
r = ∛-64
r = -4
so second term is
t₂ = -2· (-4)²⁻¹ = 8
third term is
t₃ = -2 · (-4)³⁻¹ = -32
Assuming it's factorization/simplify
If you have any questions, feel free to ask.
Answer:
The answer to your question is letter D. 24 hours
Step-by-step explanation:
Data
Nikki + Kara = 8 hours
Kara = 12 hours
Nikki = ?
Process
1.- Calculate the time Nikki painted in 1 hour
Nikki and Kara painted the fence in 8 hours then, in 1 hour the painted 1/8
Kara paint the fence in 12 hours then, in 1 hour she painted 1/12
The Kara painted in 1 hour:
Kara = 1/8 - 1/12
Kara = (3 - 2) / 24 = 1/24
2.- Calculate the time
Then in 1 hour she painted 1/24 of the fence, all the fence was painted in
(1/24)24 = 1 which means 24 hours.
I used the Old Change New method and I crossed multiplied.
The answer is about $498 (I rounded $497.895875)
Check: $498>459.95 by 8.25%
X=0
Y=-2
Multiply the top equation by -2 to get -2y=-8x+4
Isolate 2y on the bottom by subtracting 3x from both sides to get 2y = -4 - 3x
Add the two equations get 0=-11x so x = 0
Solve for y by plugging zero into one of the equations to get y=4(0)-2 to find the y = -2
y=4(0)-2
