You need to solve a system of equations. You decide to use the elimination method. Which of these is not allowed?
2x-3y=12 -x+2y=13
A. Multiply equation 1 by 2 and equation 2 by 3. Then add the new equations.
B. Multiply the left side of equation 2 by 2. Then subtract the result from equation 1
C. Multiply equation 2 by -2. Then add the result to equation 1.