Final answer:
To solve the system of equations, the method of elimination can be used. The solution is x = 3 and y = 3.
Step-by-step explanation:
To solve the system of equations:
3x - y = 6
6x + y = 21
we can use the method of elimination. By adding the two equations together, the y term will cancel out:
9x = 27
x = 3
Substituting the value of x back into one of the original equations, we can find the value of y:
3(3) - y = 6
9 - y = 6
y = 3
Therefore, the solution to the system of equations is x = 3 and y = 3.