To solve this question we will use the following diagram:0
Let x ft be the length the ladder needs to be to make it to the top of the wall.
Using the Pythagorean Theorem we get:

Simplifying the above equation we get:

Therefore:
![\begin{gathered} x^2=1000, \\ x=\sqrt[]{1000}, \\ x=10\sqrt[]{10}. \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/sprrrwh0vchgsp7auuh56pkkd63u7cd588.png)
Therefore, the length of the ladder must be:
![10\sqrt[]{10}ft.](https://img.qammunity.org/2023/formulas/mathematics/college/m6kip1ut0n9cj90srq8vrbaxy93v90q5ch.png)
Answer:
![10\sqrt[]{10}ft.](https://img.qammunity.org/2023/formulas/mathematics/college/m6kip1ut0n9cj90srq8vrbaxy93v90q5ch.png)