a We are given the following radical equation
![2\sqrt[]{n}=n-3](https://img.qammunity.org/2023/formulas/mathematics/college/lkxretc2brq72c83n8q0mx2s9pj6dx1p30.png)
To solve this equation we need to square both sides of the equation
![\begin{gathered} (2\sqrt[]{n})^2=(n-3)^2 \\ 4n=(n-3)^2 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/3p9g9d7jz5wbvoviumxlcornosp5jrz2jz.png)
Apply the squares formula on right-hand side of the equation

So the equation will become

So we are left with a quadratic equation.
The standard form of a quadratic equation is given by

Comparing the standard equation with our equation we get the following coefficients
a = 1
b = -10
c = 9
Now recall that quadratic formula is given by