Which graph represents f(x)= 4*5 x ?

y  =  f(x)  =  4 * 5^x

 

5  >  1 , so  y  will get bigger as  x  gets bigger.  That rules out the fourth graph.

 

And...

 

f(0)  =  4 * 5⁰  =  4 * 1  =  4       So the graph passes through the point  (0, 4) .

 

That rules out the first and third graph.

 

The second one has to be the right graph.