Solve for a
a=19
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3a+5+a=81
Combine a and 2a to get 3a.
4a+5=81
Combine 3a and a to get 4a.
4a=81-5
Subtract 5 from both sides.
4a=76
Subtract 5 from 81 to get 76.
a=\frac{76}{4}
Divide both sides by 4.
a=19
Divide 76 by 4 to get 19.
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Limits
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