Solve for n
n=-5
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-21n-5=100
Square both sides of the equation.
-21n-5-\left(-5\right)=100-\left(-5\right)
Add 5 to both sides of the equation.
-21n=100-\left(-5\right)
Subtracting -5 from itself leaves 0.
-21n=105
Subtract -5 from 100.
\frac{-21n}{-21}=\frac{105}{-21}
Divide both sides by -21.
n=\frac{105}{-21}
Dividing by -21 undoes the multiplication by -21.
n=-5
Divide 105 by -21.
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