Someone help with math: For which equation is b = 5 not the solution?

options:

1. 8 - b = 13
2. b + 6 = 11
3. b + 4 = 9
4. 12 - b = 7

Do not comment if you aren’t going to . create a real-life situation and create a system and show how it might be modeled algebraically with a system of equations (or inequalities) show all work include a few sentences explaining the situation, your variables of choice and what each represents, and how you would set it up and solve it algebraically. !

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