ANSWER
x = 8 in
Step-by-step explanation
We have to find x. We know the side length of one side - which is 6 in - and we can find the side length of the hypotenuse, because we know that the figure below the triangle is a square and we're given its area. The area of a square is its side length squared:
![\begin{gathered} A=L^2 \\ 100in^2=L^2 \\ L=\sqrt[]{100} \\ L=10in \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/3r0k3wdgstc1e4qnyexk6x3prsv6t17a2w.png)
Now, using the pythagorean theorem we find x:
![\begin{gathered} 10^2=x^2+6^2 \\ x=\sqrt[]{10^2-6^2} \\ x=\sqrt[]{100-36} \\ x=\sqrt[]{64} \\ x=8 \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/gi33hng2pyjy4m1nh12n27t6ndwjyfdvgh.png)