WILL GIVE BRAINLIST WHEN I CAN, SOMEONE PLEASE HELP

Answer:
slope BD = - 1
Step-by-step explanation:
Calculate the slope m using the slope formula
m = (y₂ - y₁ ) / (x₂ - x₁ )
with (x₁, y₁ ) = B(0, a) and (x₂, y₂ ) = D(a, 0)
m = [tex]\frac{0-a}{a-0}[/tex] = [tex]\frac{-a}{a}[/tex] = - 1