Which exponential equation is equivalent to the logarithmic equation below? log 784 = a

The general form of logarithmic function is y = x 
We can transform it to exponential function by following the general form of exponential function y = 

we have: 

b = 10   ⇒ if the base of logarithm is not given, its default value is 10
x = a
y = 784

our exponential form in this is 

784 = 

It will be a whole number.