Big Five Equations #4 (Blog 11)

How to derive equation number four from a graph.
Equation 4 is d = V2Δt - ½aΔt².

The area of the rectangle drawn on the graph is d = V2Δt.
The area of the triangle formed above the line V1 to V2 is d = ½ (V2 - V1) (Δt).
Therefore, the displacement equals the area of the rectangle minus the area of the triangle.
d = V2Δt - ½ (V2 - V1) (Δt).
From equation 1 (from the big five), V2 - V1 = aΔt.
Sub equation 1 into displacement equation:
d = V2Δt - ½ (aΔt) (Δt)
d = V2Δt - ½aΔt²