For us to be able to determine if the function is increasing, decreasing or constant, we will be considering the following rules:
f(x)=mx+b is an increasing function if m > 0.
f(x)=mx+b is a decreasing function if m < 0.
f(x)=mx+b is a constant function if m = 0.
The given function y = -5x + 1. Under slope-intercept form y = mx + 5, it appears that the slope of y = -5x + 1 is -5.
-5 is less than 0
Therefore, we can say that the function is strictly decreasing.