9000 is a 4 digit number that is divisible by 9 and 8. ( 9000/9 = 1000) and ( 9000/8 = 1125 )
The answer would be -0.512
You would get this answer because -0.8 times -0.8 equals 0.64. Positive 0.64 times negative 0.8 would result In -0.512
The slope cannot be found when only one co-ordinate is given.
One may assume the line is vertical or horizontal
This answer is ambiguous