Can you help write the rule for the function

In the table under "X" the numbers are -2, -1, 0, 1, 2. Under "Y" the numbers are 0, -1, -2, -3, -4

y=mx+b
as the x's increase by one, the y's decrease by 1, so m, the slope is -1/1 =1
(0,b) =(0,-2)

y=-x-2