For the simple harmonic motion equation d=5sin(pi/4(t)) , what is the maximum displacement from the equilibrium position?

5

since the amplitude given in the equation is 5

why?
well sin( ) can only be from -1 to 1, the highest displacement of just sine would naturally be 1 or -1

multiply that by the constant, youd get 5 or -5 as a displacement

if you took the absolute value, there would be no difference