Beyonce is solving a system of equations: 2x – 3y = -2
4x + y = 24
She decides to use the elimination method to find the solution. She multiplies the second equation by 3 and adds it to the first equation to find 14x = 70, showing her that x = 5. Beyonce finds that y = 4.
Step 1: 3(4x + y = 24) → 12x + 3y = 72
Step 2: 2x – 3y = -2
+ 12x + 3y = 72
14x = 70
14x/14= 70/14 → x = 5

Thinking about this process, Beyonce says out loud, “There are lots of ways I could go about solving this problem. I could do the method above or I could multiply the first equation by -2 and add the second.
Step 1: -2(2x – 3y = -2) → -4x + 6y = 4
Step 2: -4x + 6y = 4
+ 4x + y = 24
7y= 28
7y/7= 28/7 → y = 4

“I seem to find that there is only one solution to the two equations, but I wonder if I will get the same solution if I use a different method?”
If Beyonce uses a different method, would she get the same solution? Be sure to show work or explain your reasoning.

Explain how you know that a system of equations has no solution.

Explain how you know that a system of equations has an infinite number of solutions.