Given y=0.25‌sin(10πx−2πt) Comparing with equation of wave y=A‌sin(kx−ωt) A=0.25,k=10π,ω=2π ‌2π∕λ=10π‌‌2πf=2π f=1‌Hz λ=‌1∕5=0.2m When sign of coefficient of t and x are opposite it means ‌
dx
dt
=V>0 i.e., wave is propagating in the direction of growing x.