How do you find the formula of an exponential graph given (0, -2) and (2, -50)?

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Answer 1 · 2015-11-08T19:53:42

Use this model: $y = a b^{x}$ $y=ab^x$ , now solve for a and b:

$y = a b^{x}$ $y=ab^x$

Insert the x and y values into the model:

$- 2 = a b^{0} = a$ $-2=ab^0=a$

So, now we know that the coefficient $a = - 2$ $a=-2$

$- 50 = (- 2) (b^{2})$ $-50=(-2)(b^2)$

Solving for coefficient b ...

$b = 5$ $b=5$

Finally, insert both coefficients back into the model:

$y = (- 2) (5^{x})$ $y=(-2)(5^x)$

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hope that helped