Dora is building the right square pyramid shown in the diagram.
The base of the pyramid is labeled ten centimeters. A right triangle is shown within the pyramid. The height of the pyramid, which also is one leg of the right triangle, is labeled seven centimeters. The side opposite the right angle, which is also the height of the triangular face of the pyramid, is labeled k.
What is the length of k rounded to the nearest tenth of a centimeter?
Enter the correct answer in the box.
cm