Answer:
x = -4
Step-by-step explanation:
16 = 4*4 = 4²
64 = 4 * 4* 4 = 4³
[tex](\dfrac{1}{16})^{3x}=64^{2*(x+8)}\\\\\\(16^{-1})^{3x}=64^{2x + 16}\\\\\\16^{-3x}=64^{2x +16}\\\\(4^{2})^{-3x}=(4^{3})^{2x+16}\\\\4^{-6x}=4^{6x +48}[/tex]
As bases are same, compare exponents
6x + 48 = -6x
Subtract 48 from both sides
6x = -6x - 48
Add '6x' to both sides
6x + 6x = -48
12x = -48
Divide both sides by 12
x = -48/12
x = -4