Answer:
x = 15
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Move 11 to the other side, with "16" after the equal sign.
We need to subtract: 16-11 = 5
x/3 = 5
x = 5 x 3
x = 15
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To double check...
15/3 + 11 = 16
5 + 11 = 16
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PS: In algebra we actually use "*" but for the sake of it I will use "x"
Have a nice day!