Her first mistake was in Step 2. She added 0.2 to each term instead of multiplying by 0.2.
Step-by-step explanation:
CORRECT WAY:
0.2(4+1.4y - 2.1)
0.8 + 0.28y - 0.42
0.8 - 0.42 + 0.28y
0.38 + 0.28y
WHAT TAMARA DID:
0.2(4+1.4y - 2.1)
How she got 4.2: 0.2 + 4 = 4.2
How she got 1.6y: 0.2 + 1.4y = 1.6y
How she got -1.9: 0.2 + -2.1 = -1.9
WHAT SHE DID HERE IS WRONG. REMEMBER WHEN IT IS __( ______) IT MEANS THAT YOU NEED TO MULTIPLE NUMBER OUTSIDE THE PARATNESS TO EVERY NUMBER THAT IS INSIDE THE PARATNESS.
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