Answer :
slope = Δy ÷ Δx
y₂-y₁
---------
x₂-x₁
5-1
------- =
-3-1
4
----
-4
slope = -1
y-y₁ = m (x-x₁)
y-1 = -1 (x-1)
y-1 = -x + 1
y = -x + 1 + 1
y = -x + 2
y₂-y₁
---------
x₂-x₁
5-1
------- =
-3-1
4
----
-4
slope = -1
y-y₁ = m (x-x₁)
y-1 = -1 (x-1)
y-1 = -x + 1
y = -x + 1 + 1
y = -x + 2