y=-x +3 Line equation (y=mx+b)
y= -1 Line equation (constant function y= b )
1) Let's start with the first graph.
1.1) Picking two points from a linear equation is enough to find the rule for that function. So, counting we have the following points:
(0,3) and (5,-1)
1.2) Plugging those points into the slope-intercept formula:
m = -1-3/5
m=3/5
1.3) Plugging in one point into the y=mx +b
(0,3)
3=-1(0)+b
3=+b
b=0
y=-x +3
b) For the second one, this is simpler y= -1, for it is a horizontal line at point y=-1.