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I need help please! I've been stuck on this for a week and its really stressful lol

I need help please! I've been stuck on this for a week and its really stressful lol-example-1

2 Answers

3 votes

Answer:


y=0.2*4^(x)

Explanation:

Notice when x increases 1, y is 4 times the previous one, so

the function is like
y=C*4^(x)

To determine the constant C, put any pair of (x, y)

Use x = 0, y = 0.2, so

0.2 =
C*4^(0) = C * 1 = C

then
y=0.2*4^(x)

User Diceyus
by
3.6k points
6 votes

Answer:


y=(0.2)4^x

Explanation:

General form of the exponential function:
y=ab^x

Substituting the first point (0, 0.2) into the function:


\implies 0.2=ab^0

As any number to the zero power always gives one,
b^0=1


\implies0.2=a * 1


\implies a=0.2

Therefore,
y=(0.2)b^x

Substituting the second point (1, 1.8) into the function:


\implies0.8=(0.2)b^1


\implies0.8=(0.2)b


\implies b=(0.8)/(0.2)


\implies b=4

So the final exponential equation is:


y=(0.2)4^x

Checking the equation with the remaining two points:


x=2 \implies (0.2)4^2=3.2 \ \ \ \checkmark


x=3 \implies (0.2)4^3=12.8 \ \ \ \checkmark

User OrdinaryOrange
by
3.8k points