To find the length of the cable needed to support the volleyball net post, you can use the Pythagorean theorem. The situation can be visualized as a right triangle, where:
- One leg of the triangle (vertical) is the height from the court surface to the hook in the post, which is 4 ft.
- The other leg of the triangle (horizontal) is the distance from the post to the hook in the floor, which is 3 ft.
The length of the cable will be the hypotenuse of this right triangle. According to the Pythagorean theorem:
\[ c = \sqrt{a^2 + b^2} \]
where \( a \) is 4 ft, and \( b \) is 3 ft.
Calculating it:
\[ c = \sqrt{(4)^2 + (3)^2} = \sqrt{16 + 9} = \sqrt{25} = 5 \text{ ft.} \]
Thus, the length of the cable should be 5 ft.