Solve for x
x=\frac{5\sqrt{5}}{7}-\frac{1}{3}\approx 1.263858079
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21x+7=15\sqrt{5}
Add 3 and 2 to get 5.
21x=15\sqrt{5}-7
Subtract 7 from both sides.
\frac{21x}{21}=\frac{15\sqrt{5}-7}{21}
Divide both sides by 21.
x=\frac{15\sqrt{5}-7}{21}
Dividing by 21 undoes the multiplication by 21.
x=\frac{5\sqrt{5}}{7}-\frac{1}{3}
Divide 15\sqrt{5}-7 by 21.
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