Answer:
a = 9
Explanation:
5(a + 4) - 6a + 1 = 12
5a + 20 - 6a + 1 = 12
5a - 6a + 20 + 1 = 12
-1a + 21 = 12
-21 -21
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-1a = -9
/-1 /-1
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the steps are in the answer above me