Here is your solution bud!
-a/(-3)+13 = 16
if both b and c are in the denominator here is your answer
-a/-10 = 16
-a/-10 x 10 = 16 x 10
a = 160
now if b and c are seperate here is your solution
-a/(-3) + 13 = 16
-a/(-3) + 13 - 13 = 16 - 13
-a/(-3) = 3
negative numerator + denominator = positive
a/3 = 3
a/3 x 3 = 3 x 3
a=9
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