The formula for any geometric sequence is an = a1 · rn - 1, where an represents the value of the nth term, a1 represents the value of the first term, r represents the common ratio, and n represents the term number. What is the formula for the sequence -3, -6, -12, -24, ...? an = -3 · 2 n - 1
an = -3 · (-2) n - 1
an = 2 · (-3) n - 1
an = -2 · (-3) n - 1

an = -3 · 2^n - 1

Step-by-step explanation:

In a geometric series, the consecutive terms differ by a common ratio. The formula for determining the nth term of a geometric progression is expressed as

an = a1 × r^(n - 1)

Where

a1 represents the first term of the sequence.

r represents the common ratio.

n represents the number of terms.

Looking at the given sequence,

a = - 3

r = - 6/ - 3 = 2

Therefore, the formula for the sequence is

an = - 3 × 2^(n - 1)

3

step-by-step explanation:

in standard form:

a= dictionaries

b= maps

you have to buy 3 dictionaries, so put a 3 next to the a (dictionaries) so that you can multiply them by each other.

a3+b= 60 (the amount of money you have)

we already know the cost of a=15 so replace a with $15

($15 x 3)+b=60

multiply 15 and 3 to get $45 and replace it with $45

45+b=60

and then replace b with 15 to get the total:

45+15=60

that means you have $15 left after buying 3 dictionaries.

15 divided by the cost of a map ($5) equals 3.

so you can buy 3 maps.

sorry if it was confusing!