Grade 8 Math · Expressions & Equations

Recognize infinitely-many-solution equations

Recognize when both sides simplify identically and every real number is a solution.

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What you’ll learn

Recognize when both sides simplify identically and every real number is a solution.

Key idea

If simplifying both sides leaves the same expression, the equation is true for every real value of x. A true statement such as 5 = 5 places no restriction on x, so there are infinitely many solutions.

Worked example

Solve. Show equivalent steps or enter No solution / All real numbers.

(6)x + (30) = (30) + (6)x

  1. (6)x + (30) = (6)x + (30)
  2. 30 = 30

Answer: All real numbers

Quick Check

Analyze the proposed student response. Choose Correct or Incorrect.

7(x + (-5)) = (7)x + (-35) Student response: All real numbers

Choose one answer

Show a hint

What remains when the variable terms cancel?