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The table of ordered pairs gives an exponential function.

Write an equation for the function. NEED ASAP!!!

The table of ordered pairs gives an exponential function. Write an equation for the-example-1
User Dplante
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1 Answer

16 votes
16 votes

Answer:


y=4\cdot \left((1)/(3)\right)^x

Explanation:

The general form of an exponential function is:


\boxed{\begin{array}{l}\underline{\textsf{General form of an Exponential Function}}\\\\\large\text{$f(x)=a\cdot b^x$}\\\\\textsf{where:}\\\phantom{ww}\bullet\;\textsf{$a$ is the initial value ($y$-intercept).}\\ \phantom{ww}\bullet\;\textsf{$b$ is the base (growth/decay factor) in decimal form.}\end{array}}

The y-intercept is the point at which a graph intersects the y-axis, so where the x-coordinate is zero. Therefore, to find the initial value (a) from the given table of values, identify the y-value that corresponds to x = 0. So:


a = 4

As the x-values in the table increase by a constant value of one, to find the base (b) of the exponential function, we divide a y-value by the preceding y-value:


b=(4)/(12)=(1)/(3)

Therefore, the equation of the exponential function that models the given table of values is:


\large\boxed{\boxed{y=4\cdot \left((1)/(3)\right)^x}}

User Meilke
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