Slope intercept form:
y= mx + b
Where:
m= slope ( rise/run)
b= y-intercept ( where the line crosses the y axis )
We can see that the equation crosses the y axis at y= 1 , b = 1
And it goes down 1 unit for every 5 units to the right (m= -1/5)
y= -1/5x + 1