Question 7: Given the expression: \(\left| {\sqrt x – 3} \right| + 3 = {\rm{ 9}}\).Find the value of x

We have: \(\begin{array}{l} \left| {\sqrt x – 3} \right| + 3 = {\rm{ 9}}\\ \Rightarrow \left| {\sqrt x – 3} \right| = 6\\ \Rightarrow \left[\begin{array}{l}\sqrtx-3=6\\\sqrtx-3=-6\end{array}\right\Rightarrow\left[\begin{array}{l}\sqrtx=9\\\sqrtx=-3(type)\end{array}\right\\\Rightarrow\sqrtx=9\Rightarrowx=81\end{array}\)

so x= 81