MathematicsBeginner

Checking your answers

Check with the inverse operation

Estimated time · 7 min 9 Content blocks

Core concepts

Formulas

a+b=c  ⟺  c−b=a,a−b=c  ⟺  c+b=aa+b=c \iff c-b=a,\qquad a-b=c \iff c+b=a

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Exercises

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Prerequisites

Three-digit addition and subtraction9 min
Practice set
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