slope intercept is y=mx+b
m=slope
b=yint
find slope
the slope for 2 points (x1,y1) and (x2,y2) is
(y2-y1)/(x2-x1)
A.
(-1,1) and (0,3)
slope=(3-1)/(0-(-1))=2/1=2
y=2x+b
find b
(-1,1)
x=-1 an y=1
1=2(-1)+b
1=-2+b
add 2
3=b
y=-2x+3
B.
(1,5) and (3,3)
slope=(3-5)/(3-1)=-2/2=-1
y=-x+b
(3,3)
3=-3+b
add 3
6=b
y=-x+6
A. y=-2x+3
B. y=-1x+6