Answer:

Step-by-step explanation:
Since we know -7x=y we use the substitution method and plug it in the top equation.



or x=-2/3
Then plug it back in the the bottom equation

y=14/3
Volume of the first dwarf planet (r₁ = 832 mi):

Volume of the second dwarf planet (r₂ = 829 mi):

So difference between the volumes is:

or if we want exact value (we use (a³-b³) = (a-b)(a²+ab+b²) ):
Answer:
I believe the answer is D
Step-by-step explanation:
The answer is 3 1/2 or in decimal form it is 3.5