A $6 \mathrm{ft}$ thick slice is cut off the top of a cube, resulting in a rectangular box that has volume $68 \mathrm{ft}^{3}$. Use the ALEKS graphing calculator to find the side length of the original cube. Round your answer to two decimal places. $\square \mathrm{ft}$

Step 1 ：Let's denote the side length of the original cube as \(x\).

Step 2 ：The volume of the original cube is \(x^3\).

Step 3 ：After a 6 ft thick slice is cut off the top of the cube, the height of the rectangular box becomes \(x-6\).

Step 4 ：The volume of the rectangular box is \(x^2(x-6)\), which is given as 68 ft³.

Step 5 ：So we have the equation \(x^2(x-6)=68\).

Step 6 ：Solving this equation, we get \(x^3-6x^2=68\).

Step 7 ：Rearranging the equation, we get \(x^3-6x^2-68=0\).

Step 8 ：Solving this cubic equation, we get \(x \approx 7.18\).

Step 9 ：So the side length of the original cube is approximately 7.18 ft.