Step 1 :The addition method involves manipulating the equations such that when they are added together, one of the variables cancels out. In this case, we want to eliminate \(x^{2}\). To do this, we need to make the coefficients of \(x^{2}\) in both equations equal so that they cancel out when the equations are added together.
Step 2 :The coefficient of \(x^{2}\) in the first equation is 3 and in the second equation is 6. If we multiply the first equation by 2, the coefficient of \(x^{2}\) in the first equation becomes 6, which is equal to the coefficient of \(x^{2}\) in the second equation.
Step 3 :Therefore, we should multiply the first equation by 2.
Step 4 :Final Answer: We should multiply the first equation by \(\boxed{2}\).