Find the solutions to 16^x - 25*4^x + 24 = 0.
Let u = 4^x, so the equation becomes:
u^2 -25u +24 = 0 This factorises as (u - 24)(u - 1) = 0 so u = 24 and u = 1
Hence we have 4^x = 24 and 4^x = 1
Can you take it from here? (Think about taking logs of both sides)
