Solve for r
r=0
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\sqrt{7r+4}=2
Swap sides so that all variable terms are on the left hand side.
7r+4=4
Square both sides of the equation.
7r+4-4=4-4
Subtract 4 from both sides of the equation.
7r=4-4
Subtracting 4 from itself leaves 0.
7r=0
Subtract 4 from 4.
\frac{7r}{7}=\frac{0}{7}
Divide both sides by 7.
r=\frac{0}{7}
Dividing by 7 undoes the multiplication by 7.
r=0
Divide 0 by 7.
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