we only need two points:
(1,1)
(2,-2)
Point slope form:
Given a point (x₀,y₀) and the slope m, the point -slope form is:
y-y₀=m(x-x₀)
If we wante to find out the slope:
Given two points:
(x₁,y₁)
(x₂,y₂)
The slope is:
m=(y₂-y₁) / (x₂-y₁)
In this case:
(1,1)
(2,-2)
m=(-2-1) / (2-1)=-3
We have a point (1,1) and the slope m=1
The point-slope form is
y-1=-3(x-1)
y-1=-3x+3
y=-3x+3+1
y=-3x+4
Answer: y=-3x+4