What are the solutions to the system of equations graphed below? a. (–2, 0) and (2, 0) b. (0, 2) and (–4, 0) c. (2, 0) and (0, –4) d. (0, –2) and (0, 2)

You haven't provided the graph, therefore, I cannot give an exact answer.
However, I will help you with the concept.

A solution to a system of equations would be one or more order pairs that satisfy ALL equations given in the system.

There are two ways to get the solution of a system of equations:
1- algebraically: 
This would be by solving the equations in the system simultaneously using elimination/substitution,...etc

2- graphically:
This would be by graphing all the equations given in the system and finding the points of intersection between the graphs.
Note that:
If the given system has two equations, then we need to find the point(s) of intersection between the two graphs
If the given system has three equations, then we need to find the point(s) of intersection between the three graphs

Therefore, for your question, all you have to do is find the point(s) of intersection between your graphs.

Hope this helps:)

Do you need with the x value for the minimum? its always between the two intercepts for a parabola

Hello!
volume of sphere =4/3.pi.r^3