Answer:
5 meters
Step-by-step explanation:
The room is rectangular, so the two walls and the diagonal (distance between opposite corners) form a right triangle.
We can use [tex]a^2 + b^2 = c^2[/tex] to compute the other wall's length:
[tex]13^2 = 12^2 + x^2\\169 = 144 + x^2\\25 = x^2\\x = \pm 5[/tex]
