Two terms in a geometric sequence are a3=729 and a4=243.What is the first term of the sequence, and what is the recursive rule that describes the sequence?

Answers

Answer 1
Answer:

The first term of the given sequence (a) = 6561

Step-by-step explanation:

Let the first term = a and common difference = d

Given,

a_(3) = 729 and a_(4) = 243

To find, the first term of the given sequence (a) = ?

We know that,

The nth term of a G.P.

a_(n) =ar^(n-1)

The 3rd term of a G.P.

a_(3) =ar^(3-1)

ar^(2) = 729          ..............(1)

The 4th term of a G.P.

a_(4) =ar^(4-1)

ar^(3) = 243          ..............(2)

Dividing equation (2) by (1), we get

(ar^(3))/(ar^(2)) = (243)/(729)

r=(1)/(3)

Put r=(1)/(3) in equation (1), we get

a((1)/(3))^(2) = 729    

a((1)/(9)) = 729    

⇒ a = 9 × 729 = 6561

∴ The first term of the given sequence (a) = 6561

Answer 2
Answer:

Final answer:

The first term of the geometric sequence is 6561 and the recursive rule of the sequence is a(n) = a(n-1) * 1/3.

Explanation:

In a

geometric sequence

, each term after the first is found by multiplying the previous term by a fixed, non-zero number called the

common ratio

. In your case, you are given the third term, a3=729, and the fourth term, a4=243 in the sequence. We know that in a geometric sequence, any term divided by the previous term gives the common ratio. So 243/729 = 1/3, which is the common ratio, r.

Now, to find the first term, we use the provided values and the formula for the nth term in a geometric sequence which is a = a3 / r^n, where a is the first term, r is the common ratio, and n is the term number. Therefore, to find the first term, we go back two steps from the third term (729) dividing by 1/3 each time: (729/1/3) = 2187 (which is the second term) and again (2187/1/3) = 6561 (which is the first term).

So, the first term, a1=6561, and the recursive rule that describes this sequence is a(n) = a(n-1) * 1/3

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The sum of two rational numbers is -7. if one of the numbers is –15/19, the other number is

Answers

Answer: the other rational number is 118/19

Answer:

-118/19

Step-by-step explanation:

let x, y = the two rational numbers, respectively.

What do we know?

  • x + y = -7
  • x = -15/19

Step one: Plug in the values:

-15/19 + y =-7

Step two: Isolate the variable by adding 15/19 on both sides

y = -7 +15/19

Step three: Simplify the right side

Use basic addition to add the two numbers:

y = - 118/19

$65 digital camera marked up 50%

Answers

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or
65 x 1.5 = 97.5...

just remember to keep to the basics!

URGENT,PLEASE HELP ME !!!!!!!!!!!!!!!

Answers

Answer: The last one

Step-by-step explanation:

I think this because the graph starts from H the number of hours studied and when u add the numbers and divide them up which gives you the equation 65 + 50 . Any questions please text me. Have a nice day.

2x+6 less than or equal to -4

Answers

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Answers

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Distributive property.

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Combine like terms.

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Distributive property.

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Combine like terms.

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Isaiah put a kilogram on a balance pan. how many 100 gram weights does he need too balance the scale

Answers

1 kilogram = 1000 grams
100g • 10 = 1000g
Isaiah would need to put 10 100 gram weights on the scale in order for it to equal 1 kilogram.

Final answer:

Isaiah would need to place 10 units of 100 gram weights on the balance scale to counterbalance the kilogram. This is because a kilogram equates to 1000 grams and each weight is 100 grams.

Explanation:

To determine how many 100 gram weights are needed to balance a scale with a kilogram on the other side, we first need to understand that a kilogram (kg) is equivalent to 1000 grams (g). This is based on the metric system, where the prefix 'kilo-' signifies a factor of 1000.

Therefore, if Isaiah has a kilogram on one side of the scale, he has a mass of 1000 grams to balance. Given that the weights he is using are each 100 grams, he would need to use 10 of these weights to balance the mass on the scale. This because 100 (grams per weight) times 10 (weights) equals 1000 grams which is equal to the kilogram placed on the other side.

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