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An exponential function f ( x ) = a b x passes through the points (0, 2000) and (2, 720). what are the values of a and b ?

User Rozzy
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1 Answer

2 votes

Answer:

a = 2000 , b = 0.6

Explanation:

given the equation of the exponential has the form

y = f(x) = a
b^(x)

use the coordinates of the points f(x) passes through

using (0, 2000 ) , then

2000 = a
b^(0) [
b^(0) = 1 ]

2000 = a × 1 = a , then

y = 2000
b^(x)

using (2, 720 )

720 = 2000 b² ( divide both sides by 2000 )

0.36 = b² ( take square root of both sides )


√(0.36) = b

b = 0.6

so a = 2000 and b = 0.6

User Chris Mueller
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