Mississippi Math FA.A.11

MathGrades 9–12Algebra (A) Equations and Inequalities

The Standard

Justify when linear equations in one variable will yield one solution, infinitely many solutions, or no solution. (8.EE.7a)

2025 Mississippi College- and Career-Readiness Standards for Mathematics

Teacher's field guide

What Students Need to Do: Students simplify linear equations with a variable on both sides. They use the result to explain whether one value, every value, or no value makes the equation true.
What Mastery Looks Like: A student can show that an equation leads to a value for x, a true statement such as 6 = 6, or a false statement such as 6 = 7. They can explain why those results mean one solution, infinitely many solutions, or no solution.
Common Misconceptions: Students may call 0 = 0 no solution because the x disappeared. They may treat 0 = 1 as a value for x, or assume that any equation with x on both sides has one solution.
How to Assess It: On an exit ticket, ask students to classify 3(x + 2) = 3x + 6, 3(x + 2) = 3x + 7, and 3(x + 2) = x + 6. Have them show the step that proves each answer.

Lesson moves

Give pairs paper cups for x and counters for 1; model 2x + 4 = x + 7, 2x + 4 = 2x + 4, and 2x + 4 = 2x + 5.
Ask, 'Why does 4x + 3 = 4x + 3 have every number as a solution, while 4x + 3 = 4x + 5 has none?'
Play a three-bin card sort with 5x + 2 = 17, 5x + 2 = 5x + 2, and 5x + 2 = 5x + 4; require a reason for each placement.
Compare two taxi plans, each charging $3 per mile, with starting fees of $5 and $7; ask when their costs match.

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