Answer:
[tex]\frac{7\sqrt{2}}{2}[/tex]
Step-by-step explanation:
In the picture the 2 adjacent sides appear to be congruent.
So let's label one - x, so the other one is also x.
And using Pythagoras' Theorem.
[tex]x^2 + x^2 = 7^2\\2x^2 = 49\\x^2 = \frac{49}{2}\\x = \frac{7}{\sqrt{2}}\\x = \frac{7\sqrt{2}}{2}[/tex]
