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hodyreva [135]
3 years ago
7

Solve 2a + 21 = 8a - 9, step by step

Mathematics
1 answer:
Rom4ik [11]3 years ago
6 0
2a + 21 = 8a - 9

Combine like terms. 

2a + 21 = 8a - 9
-2a          -2a

21 = 6a - 9 
+9          +9

30 = 6a
6a/6 = 30/6
a = 5

Answer: a = 5
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Work Shown:

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