Which of the following is the best first step to solve the following system of equations using elimination?

Question

Which of the following is the best first step to solve the following system of equations using ELIMINATION?

6x+2y=−2

3x+3y=9

A. Add the two equations together to eliminate the x variable.

B. Multiply the equation 3x+3y=9 by −2.

C. Multiply the equation 3x+3y = 9by 3.

D. Divide the equation 3x+3y = 9 by 3.

(Answer needed ASAP)

Answer 1

Elimination means we want to add the two equations together to eliminate one of the variables. (basically one should be x and the other -x)

B is the only answer that does this.

(3x+3y) *2 =9* (-2) * 2 = -6x - 6y = -18

First equation has 6x and second has -6x,

Answer 2

B.) is the best first step to solve the above system of equations. By multiplying the bottom equation by -2, we end up with an equation of -6x - 6y = -18. We can then add the first and second equations together, and the "x" terms will cancel each other out, giving us a neat answer of -4y = -20. We can then easily solve for y, and plug that value of y into any of the two original equations to find the value of x.