Answer and Step-by-step explanation:
The answer is attached below
21 I think cause you use pemdas
Answer:

Step-by-step explanation:
We need to simplify out the given exponential expression . The given expression to us is ,
We can use the <u>Law of </u><u>Exponents</u> to simplify the given expression . Recall that ,

Note that , we can write ,
Therefore our expression becomes ,
Simpify using the Law of Exponents ,
Open the brackets in exponent ,
Simplify to get final expression ,

Answer:
The answer is f(x) = 0.8(2^x)
Step-by-step explanation:
∵ f(x) = 0.8(2^x)
∵ x = -2 ⇒ ∴ f(-2) = 0.8(2^(-2)) = 0.2
∵ x = -1 ⇒ ∴ f(-1) = 0.8(2^(-1)) = 0.4
∵ x = 0 ⇒ ∴ f(0) = 0.8(2^(0)) = 0.8
∵ x = 1 ⇒ ∴ f(1) = 0.8(2^(1)) = 1.6
∵ x = 2 ⇒ ∴ f(2) = 0.8(2^(2)) = 3.2
∴ The answer is f(x) = 0.8(2^x) ⇒ The fourth answer
If you divide 21 by 7 you get 3 so you divide 27 by 3 to get 9 so the ratio 21 to 27 is equivalent to the ratio of 7 to 9