Write the explicit formula that represents the geometric sequence -2, 8, -32, 128

1 answer:

6 0

So hmm the first term is -2

and if we divide one term by the term before it, we'd get the "common ratio" "r"

so hmm say -32/8 that gives us -4, so r = -4

thus $\bf n^{th}\textit{ term of a geometric sequence}\\\\
a_n=a_1r^{n-1}\qquad 
\begin{cases}
a_1=\textit{first term}\\
r=\textit{common ratio}\\
----------\\
a_1=-2\\
r=-4
\end{cases}\implies a_n=-2(-4)^{n-1}$

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the Jelly Junior High School color is made by mixing red paint with yellow paint . the ratio of red to yellow is 3 to 5 . how mu

GarryVolchara [31]

To get the answer we can use proportion
3 red ----------------- 5 yellow
x red ----------------- 20 yellow
Crossmultiply now
3*20=5x
60=5x /:5 (divide both sides by 5)
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3 years ago

The circle below is centered at the point (3,1) and has a radius length of 2.What is its equation

hammer [34]

Answer:

C. $(x-3)^2+(y-1)^2=2^2$

Step-by-step explanation:

The standard equation of a circle, given the radius r units and center (h,k) is given by:

$(x-h)^2+(y-k)^2=r^2$

From the question, we have the center of the circle to be (3,1) and the radius is 2 units.

We substitute the center and radius of the circle into the equation to get:

$(x-3)^2+(y-1)^2=2^2$

The correct answer is C

7 0

3 years ago

A Ferris will can accommodate 45 people in 15 minutes. How many people could ride the Ferris wheel in three hours?

anzhelika [568]

Answer:

540 people

Step-by-step explanation:

First, to get the minutes to hours you have to multiply 15 by 4 because there are 4 sets of 15 minutes in an hour. You get 180 people an hour.

Now you have to get to three hours so you have to multiply 180 by 3 so you get 540 people for 3 hours because when you multiply an hour by 3 you get three hours.

That's why the answer is 540 people in 3 hours.