2.CE.1.g
Determine the missing number in an equation (number sentence) through modeling and justification with addition and subtraction within 20 (e.g., 3 + __ = 5 or __ + 2 = 5; 5 – __ = 3 or 5 – 2 = __).
Example Problems
Solve the equation:
Solve the equation:
Solve the equation:
Khan Academy ResourcesSubtract within 100 using place value blocksAdd within 20Add within 100 using place value blocksSubtract within 20Subtract within 20 visuallyAdd within 100 using a number lineAdd & subtract within 20Add within 20 visuallyFind the missing number (add and subtract within 100)Subtract within 100 using a number lineAdding 7 + 6Addition and subtraction word problems: superheroesMissing numbers in addition and subtractionSubtract within 20 using place value blocksAdding 8 + 7Subtracting 14 - 6Adding within 20 using place value blocksAddition and subtraction word problems: gorillasAdding within 20 using ten frames

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