B
calculate the slopes m of the 2 lines using the gradient formula
m = (y₂ - y₁ ) / (x₂ - x₁ )
with (x₁, y₁ ) = C(- 2, 4) and (x₂, y₂ ) = D(0, - 4 )
[tex]m_{CD}[/tex] = [tex]\frac{-4-4}{0+2}[/tex] = [tex]\frac{-8}{2}[/tex] = - 4
repeat with (x₁, y₁ ) = F(- 4, 0 ) and (x₂, y₂ ) = G(4, 2 )
[tex]m_{GF}[/tex] = [tex]\frac{2-0}{4+4}[/tex] = [tex]\frac{2}{8}[/tex] = [tex]\frac{1}{4}[/tex]
The 2 lines are perpendicular because their slopes are negative reciprocals
