Choose the ordered pair that is a solution to the system of equations.

3x - y = 9
2x + y = 6

(3,0)
(3,-18)
(3,-1)
(3,1)

Once again add the two equations to get
5x = 15
Solve for x and substitute into either equation to find y.

To find the solution to the system of equations, we can use the method of addition or elimination. Let's use the addition method.

Given equations:
1) 3x - y = 9
2) 2x + y = 6

First, we need to eliminate the variable "y" by adding the two equations together. The y term will cancel out.

Adding the equations gives us:
(3x - y) + (2x + y) = 9 + 6
Simplifying:
5x = 15

Now, we can solve for x by dividing both sides of the equation by 5:
x = 15/5
x = 3

To find the value of y, we can substitute the value of x (3) into either of the original equations. Let's use the first equation:
3(3) - y = 9
9 - y = 9
Subtracting 9 from both sides:
-y = 0
y = 0

So the solution to the system of equations is (3, 0).

Now let's check the given options:
1) (3, 0) - This is the solution we found.
2) (3, -18) - This doesn't satisfy either equation.
3) (3, -1) - This doesn't satisfy the second equation.
4) (3, 1) - This doesn't satisfy the second equation.

Therefore, the only solution that satisfies both equations is (3, 0).