Solve for a
a = -\frac{5}{2} = -2\frac{1}{2} = -2.5
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25+2a=20
Swap sides so that all variable terms are on the left hand side.
2a=20-25
Subtract 25 from both sides.
2a=-5
Subtract 25 from 20 to get -5.
a=\frac{-5}{2}
Divide both sides by 2.
a=-\frac{5}{2}
Fraction \frac{-5}{2} can be rewritten as -\frac{5}{2} by extracting the negative sign.
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