Question

Which equation results from adding the equations in this system?

-2x+y = 8
5x-y=-5
O 7x=13
O 7x=3
O 3x=3
3x= 13

Answer 1

Answer: 3x=3

Explanation: Let's divide this into parts--

1. Adding the x variables: -2x+5x or 5x-2x = 3x.

2. Adding the y variables: y-y or -y+y = 0. (The negative and the positive y cancel each other out.)

3. Adding the numbers: 8-5 or -5+8 = 3.

Now just put it back into an equation: 3x + 0 = 3.

We don't need to add the 0, so the equation changes into 3x = 3.