Solve for k
k=84
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2k+1=169
Square both sides of the equation.
2k+1-1=169-1
Subtract 1 from both sides of the equation.
2k=169-1
Subtracting 1 from itself leaves 0.
2k=168
Subtract 1 from 169.
\frac{2k}{2}=\frac{168}{2}
Divide both sides by 2.
k=\frac{168}{2}
Dividing by 2 undoes the multiplication by 2.
k=84
Divide 168 by 2.
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