Margie's work for adding linear expressions is shown below. After checking her answer with the answer key, she solved it incorrectly.
Given (β3.78b + 12) β (4.82b β 16)
Step 1 β3.78b + 12 + β4.82b β 16
Step 2 β3.78b + β4.82b + 12 β 16
Step 3 (β3.78b + β4.82b) + (12 β 16)
Step 4 β8.6b + (β4)