Question

Find the equation of the exponential

function represented by the table below:
X
0
1
2
3
Y
5
20
80
320

Answer 1

y = 5
`(4)^(x)`

Explanation:

the equation of an exponential function in standard form is

y = a
`b^(x)`

use ordered pairs from the table to find values of a and b

using (0, 5 )

5 = a
`b^(0)` [
`b^(0)` = 1 ] , then

5 = a

y = 5
`b^(x)`

using (1, 20 )

20 = 5
`b^(1)` = 5b ( divide both sides by 5 )

4 = b

then

y = 5
`(4)^(x)` ← equation of exponential function