scan your graph and post it,
transformations are easy. in the form y=ab^x + c. c is the vertical displacement, it can be up or down (ex, if c= -2 shift your graph down 2 units.)
a is whether the graph is reflected in the x axis or stretched/compressed vertically. (if its 1 the graph doesnt change, if its -3 then reflect the graph in the x axis and stretch it by a factor of 3)
b determines whether the graph will be exponential growth, or exponential decay. google it. (its never negative)
if x has a negative sign in front of it then the graph is reflected in the y axis. (ex. -x + 3 will be a (in order) a shift to the left by 3 and THEN a reflection in the y axis.)
so if your equation is y= -3(4)^x-3 +6 shift right 3, reflect in the x, then shift up 6. you find the values of c and whats around x by looking at the graph.
to find a and b use two points on the graph, plug them in the equation y=ab^x + c, you will now have 2 equations (1 and 2 ) in equation 1 solve for a, then plug that into equation 2 to solve for b. put it all together and youll have your finished equation
that probably doesnt make sense