Answer:
[tex]\frac{b}{a}[/tex]
Step-by-step explanation:
Calculate the slope m using the slope formula
m = [tex]\frac{y_{2}-y_{1} }{x_{2}-x_{1} }[/tex]
with (x₁, y₁ ) = (a, b) and (x₂, y₂ ) = (- 2a, - 2b)
m = [tex]\frac{-2b-b}{-2a-a}[/tex] = [tex]\frac{-3b}{-3a}[/tex] = [tex]\frac{b}{a}[/tex]