In an arithmetic sequence, the 10th term \((a_{10})\) is \(30\) and the common difference is \(2\). What is the 1st term \((a_1)\) ?

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Using the explicit formula for arithmetic sequences:

$$ a_n = a_1 + d(n-1) $$ $$ a_{10} = a_1 +2(10-1) $$ $$ 30 = a_1 + 2(9) $$ $$ a_1 = 30-18 $$ $$ a_1 = \boxed{12} $$