Answer: The solution is:  " a = 37 " .
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Explanation:
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Given the equation:
 a − 15 = 22 ; Solve for "a" .
Add "15" to each side of the equation; 
 to isolate "a" on one side of the equation; 
 and to solve for "a" :
 a − 15 + 15 = 22 + 15 ; 
 to get: 
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 → a = 37 .
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Hope this answer—and explanation—is helpful!
 Wishing you the best!
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