Keisha tried to evaluate an expression step by step.3−4−7=3−(4−7) Step 1=3−(−3) Step 2=6 Step 3Find Keisha's first mistake.Choose 1 answer:(A) Changing the groups changes the difference's value.(B) 4 minus 7 equals 3 , not −3(C) 3 minus −3 equals 0 , not 6.
Q. Keisha tried to evaluate an expression step by step.3−4−7=3−(4−7) Step 1=3−(−3) Step 2=6 Step 3Find Keisha's first mistake.Choose 1 answer:(A) Changing the groups changes the difference's value.(B) 4 minus 7 equals 3 , not −3(C) 3 minus −3 equals 0 , not 6.
Regrouping terms: Keisha starts with the expression 3−4−7 and rewrites it as 3−(4−7).Reasoning: She is applying the associative property of subtraction to regroup the terms.Calculation: No calculation is done in this step.Math error check:
Evaluate inside parentheses: Keisha then evaluates the expression inside the parentheses, 4−7, and gets −3. Reasoning: She is correctly subtracting 7 from 4. Calculation: 4−7=−3Math error check:
Subtracting negative: Keisha then subtracts −3 from 3, writing 3−(−3) which she evaluates as 6.Reasoning: She is correctly identifying that subtracting a negative is the same as adding the positive equivalent.Calculation: 3−(−3)=3+3=6Math error check:
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