Write an exponential function in the form y=ab^x that goes through points (0, 20) and (4,320).

Answer 1

y = ab^x

Use the 2 given points to find a and b.

20 = ab⁰ = a

a = 20

320 = 20b⁴

16 = b⁴

b = 2

y = 20 (2^x)

Test the answer.