It will be a 6 because the 8.5 is actually 8.50. So when subtracting mentally 8.50 - 4.64 you know 0 - 4 cannot be subtracted. Barrow a 1 from the 5 and now it'll be like 10 - 4. Which 10 - 4 = 6
8.50
- 4.64
= 3.86
Distance Formula: 
Point 1: (9,0)
Point 2: (5,-8)
D = sqrt[ (5 - 9)^2 + (-8 - 0)^2 ]
D = sqrt[ (-4)^2 + (-8)^2 ]
D = sqrt[ 16 + 64]
D = sqrt(80)
Hope this helps!
It 10,000,000 because there is no way that it can be in expanded form
Simplified answer would be 60k^2+k
and you get that answer by combining like terms, Good Luck!
Its math just use a calculator or something
