can you please explain how to do the following:

Find the values of a and b such that the graph of y = ae^(-bx) goes through the points (3, 50) and (6, 10).

So I put the numbers into simultaneous equations and i got

1) 50=ae^(-3b)

2) 10=ae^(-6b)

but I dont know how to solve these...

...thankyou