Answer:
d=1/2
Step-by-step explanation:

Answer:
A = 0/(0 x 7y³)
Let's see the denominator: 0 x 7y³ = 0
=> Whenever the denominator is 0, A is undefined, neither a positive number or negative number
Hope this helps!
:)
X + 8x = 81
9x = 81, x = 9
y = 8(9), y = 72
Solution: (9, 72)