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Solve one-step addition equations

One-step addition equations represent an unknown addend in a whole-number relationship, such as x+27=65x+27=65, 27+x=6527+x=65, or 27+x=6527+ x=65; solving means determining the number that makes both sides equal, often by using the inverse relationship between addition and subtraction. The understanding includes interpreting the equal sign as a balance rather than an instruction to compute, and is limited to single-step equations with whole numbers, not negative numbers, fractions, decimals, or multi-step algebraic expressions.

Detailed Explanation: Solve one-step addition equations

An addition equation shows that two amounts are equal. The letter represents the missing addend.

To find the missing number, use the inverse operation: subtraction undoes addition.

Example:

x+27=65x+27=65
  1. The whole amount is 6565, and one addend is 2727.
  2. Subtract the known addend from the whole:
65−27=3865-27=38
  1. So, the missing number is:
x=38x=38
  1. Check your answer by replacing xx with 3838:
38+27=6538+27=65

The equation is true, so the solution is x=38\boxed{x=38}.

Learn by doing: Solve one-step addition equations

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Linear Equation - One Variable, Two Terms, Simple Display


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