Negative exponents work like this:

So, in order to evaluate a negative exponent, you simply have to invert the base, and then raise to the positive equivalent of the exponent.
As an example, here are the first three exercises:



You can work out the rest applying this logic.
12.9986 would be the answer from a calculator but I'd say it's 12.9. Hope this helped!
Answer:
1) 8 : 343
2) 42.875 or 42 ⅞
3) 4 : 49
4) 16ft²
Step-by-step explanation:
Volume of cube: s³
Surface area of cube: 6s²
_____________________
32ft^3 and 1372ft^3 →
32 : 1372 = 8 : 343
343 / 8 = 42 ⅞ = 42.875
s³ → 6s²
s³ = 8, s = 2, s² = 4.
s³ = 343, s = 7, s² = 49.
These are proportional so it is already in the simplest ratio so it is not necessary to multiply by 6.
s³ → 8 : 343
6s² → 4 : 49
(4 / 49) × 196ft² = 16ft²
Answer:
Not right.
Step-by-step explanation:
m <HGJ + m <KGJ =180°
So, m <HGJ = 180° - m <KGJ = 180° - 86° =94°
Answer:
x= -54
Step-by-step explanation:
-4x - 84 = 2x + 24
-4x + 2x= 24 + 84
-2x= 108
x= 108 ÷ (-2)
x= -54