Answer:
The most appropriate method for solving the first system of equations would be elimination. This can be done by adding the two equations together, which will eliminate one of the variables and leave us with an equation in terms of the remaining variable. We can then solve for the value of this variable and substitute it back into one of the original equations to find the value of the other variable.
For the second system of equations, substitution would be the most appropriate method. This is because one of the equations can be rearranged to solve for the value of one of the variables, which can then be substituted into the other equation. This will eliminate one of the variables and allow us to solve for the value of the remaining variable.
For the third system of equations, graphing would be the most appropriate method. This is because both equations are in the form "y = mx + b," which is the standard form of a linear equation. We can graph both equations on the same coordinate plane and find the point of intersection, which will give us the values of both variables.