Final answer:
To solve a system by elimination, we change the system so that one variable cancels out, and then solve for one variable at a time.
Step-by-step explanation:
To solve a system of equations by elimination, we transform the system such that one variable cancels out. The correct answer to the question is A) Cancels. This means that we adjust the coefficients of the variables by either multiplying or adding the equations together so that the variable in question eliminates itself, resulting in an equation with a single variable which can then be easily solved. After finding the value of one variable, we substitute it back into one of the original equations to find the value of the other variable.