1. Liam is solving the following equation 12a - 4(5a - 1) = 2(3a + 6) - 4a. The result of each step of his solution is shown below.
12a - 4(5a - 1) = 2(3a + 6) - 4a
12 - 20a + 4 = 6a + 12 - 4a
-8a + 4 = 2a + 12
-6a = 8
a = -4/3
Describe the error AND solve correctly.

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