w = 3(2a + b) - 4
First, add 4 to both sides:
w (+4) = 3(2a + b) - 4 (+4)
w + 4 = 3(2a + b)
Next, divide 3 from both sides:
(w + 4)/3 = (3(2a + b))/3
(w + 4)/3 = 2a + b
Next, subtract b from both sides:
((w + 4)/3) - b = 2a + b (-b)
(w + 4)/3 - b = 2a
Finally, divide 2 from both sides:
((w + 4)/3 - b)/2 = (2a)/2
a = (((w + 4)/3) - b)/2
a = (((w + 4)/3) - b)/2 is your answer.
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