Answer:
15cm
Step-by-step explanation:
First, a square's diagonal is basically the hypotenuse of a 45-45-90 triangle. a 45-45-90 triangle has a really special relationship, where the side length is x, and the diagonal is x
. So, the side length is 15.
Since we aren't told the length of the 3rd bar, focus solely on the lengths of the first 2 bars. Add together their lengths: 1.15 cm + 3.92 cm = 5.07 cm.