Need !

a 5 inch bamboo shoot doubles in height every 3 days. if the equation y=ab^x , where x is the number of doubling periods , represents the height of the bamboo shoot, what are the values of a and b?

Answer a = 5 and b = 2.

Procedure

Initially means x = 0, then

5 = a*b^0 = a*1 = a, then a = 5

When x = 1, the height is the double of 5, i.e 10 and

10 = a.b^1 = a.b  ⇒  b = 10/a = 10/5 = 2

The a = 5 and b = 2, so the equation is y =5(2)^x