You found $5, so it's positive. You don't put anything in the negative, because you aren't losing anything.
Answer: 4
Step-by-step explanation:
x - 2y =10
x = 10 + 2y



... cancel like terms (y + 5)
= 4
The volume of a sphere is given by the equation

, where r is the radius.
We are given the diameter of the sphere, but recall that the diameter is twice the radius:

. So the radius is half of the diameter:

.
Half of 8 cm is 4 cm.
We substitute this for r in the equation and we use 3.14 for <span>π.</span>