The equation for an exponential function is y = ab^{x} where a is the initial amount,, b is the common growth/decay factor and x is the time, the independent variable.

The output ** y = v **(value in dollars, The initial amount is,

**,**

*a = 400,000***(since the value is doubling each decade) and,**

*b = 2***(time is in decades)**

*x = d*We plug in these values of y, a, b, and x in the exponential function y = ab^{x}, to get the required equation for v.

Suppose d = -2, we plug in d = -2, in the equation to get v = 400,000 \cdot 2^{-2} = \frac{400000}{4} = 100,000, and we get the value as v = $100,000. This means that the value of the home in 2013 was $100,000.

d=−2 signifies the value of the home 2 years back since 2015.

I found an answer from www.quora.com

How is the British pound stronger than the US **dollar when** there is ...

“Why is 1 pound **worth** more than 1 **dollar**?” So far I **have** read several very good
answers regarding relative **worth** today, but none of them actually answers the ...

For more information, see How is the British pound stronger than the US **dollar when** there is ...

I found an answer from en.wikipedia.org

Moore's law - Wikipedia

Moore's law is the observation that the **number** of transistors in a dense
integrated circuit (IC) **doubles** about **every** ... These step changes in digital
electronics **have been** a driving force of ... In a **2015** interview, Moore noted of the
1965 article: ". ... **House** noted that Moore's revised law of **doubling** transistor
count **every** 2 ...

For more information, see Moore's law - Wikipedia