Question

Please you can help me. Thanks

Answer 1

y =
`15(4)^(x)` or y =
`15(-4)^(x)`

Explanation:

Standard equation is: y=
`ab^(x)` ................(1)

The function passes through (0,15) and (2,240).

so, by putting x = 0 and y = 15, we get

15 =
`ab^(0)`

a = 15

Also, putting x= 2 and y= 240, we get

240 =
`ab^(2)`

240 =
`15b^(2)`

`b^(2)` =
`(240)/(15)`

`b^(2)` = 14

b = 4 or b= -4

Putting the values of a and b in (1), we get

y =
`15(4)^(x)` or y =
`15(-4)^(x)`