The correct answer is: [C]: "-2 " .
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→ " a = - 2 " .
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Explanation:
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Given: " -1a = 3a + 8 " ; Solve for "a" .
Add "1a" to each side of the equation:
→ " -1a + 1a = 3a + 1a + 8 ;
to get: 0 = 4a + 8 ;
↔ 4a + 8 = 0 ;
Subtract "8" from each side of the equation:
→ 4a + 8 − 8 = 0 − 8 ;
to get:
→ 4a = - 8 ;
Divide each side of the equation by "4" ;
to isolate "a" on one side of the equation; & to solve for "a" ;
→ 4a / 4 = -8 / 4 ;
to get:
→ a = -2 .
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The answer is: " a = -2 " .
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