Solve for x
x=13
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3\times 7=8+x
Cancel out 4 and 4.
21=8+x
Multiply 3 and 7 to get 21.
8+x=21
Swap sides so that all variable terms are on the left hand side.
x=21-8
Subtract 8 from both sides.
x=13
Subtract 8 from 21 to get 13.
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