To find out how long the cable should be, we can use the Pythagorean theorem. The situation forms a right triangle where:
- One leg (the height from the court surface to the hook) is 4 ft.
- The other leg (the horizontal distance from the base of the post to the hook in the floor) is 3 ft.
Using the Pythagorean theorem:
\[ c^2 = a^2 + b^2 \]
where \(c\) is the length of the cable, \(a\) is the vertical leg (4 ft), and \(b\) is the horizontal leg (3 ft).
Calculating:
\[ c^2 = 4^2 + 3^2 \] \[ c^2 = 16 + 9 \] \[ c^2 = 25 \] \[ c = \sqrt{25} \] \[ c = 5 \]
Therefore, the cable should be 5 ft long.