The given triangle is a right triangle as shown by the square symbol inside. With this, we can solve the length "x" of this triangle using the Pythagorean Theorem.

where c = length of the hypotenuse and "a" and "b" are any of the remaining sides.
In our triangle, we have 7 as our hypotenuse and 2 as the length of the one side. Let's apply these values in the formula above.
![\begin{gathered} 7^2=2^2+b^2 \\ 49=4+b^2 \\ 49-4=4+b^2-4 \\ 45=b^2 \\ \sqrt[]{45}=\sqrt[]{b^2} \\ \sqrt[]{45}=b \\ 3\sqrt[]{5}=b \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/qyqdo2qann4zg1mz7k0vf2ch3zpddsbcpu.png)
Therefore, the value of x is √45.