River basins by slope of triangle

VI

SA

SB

VJ SC VK

Tipping toward SA VK > (VI+ VJ) / 2

Tipping toward SB VK < (VI + VJ) / 2 and VI < VJ

Tipping toward SC VK < (VI + VJ) / 2 and VI > VJ

VA VB

VA = 100

VB = 120 VE

VC = 150

VD = 140

VC VD

Therefore VE < (VB+VD)/2 and VB > VD (not possible)

VA VB

VA = 100 VE

VB = 120

VC = 150

VD = 140

VC VD

Therefore VE < (VB+VD)/2 and VD < VB

VE < 130

VE < (VC+VD)/2 and VC > VD

VE < 145

VE < (VC+VA)/2 and VA > VC (not possible)

VA VB

VA = 100 VE

VB = 120

VC = 150

VD = 140

VC VD

Therefore VE < (VB+VD)/2 and VD < VB

VE < 130

VE < (VC+VD)/2 and VC > VD

VE < 145

VE < (VC+VA)/2 and VC > VA

VE < 125

VE > (VA+VB)/2

VE > 110

Valid configuration for 110 < VE < 125

VA VB

VA = 100 VE

VB = 120

VC = 150

VD = 140

VC VD

Therefore VE < (VB+VD)/2 and VD < VB

VE < 130

VE < (VC+VD)/2 and VC > VD

VE < 145

VE > (VC+VA)/2

VE > 125

VE > (VA+VB)/2

VE > 110

Valid configuration for 125 < VE < 130