Answer:
3. √74
Step-by-step explanation:
By the Pythagorean theorem, the length of the hypotenuse can be calculated as:
![c=\sqrt[]{a^2+b^2}](https://img.qammunity.org/2023/formulas/mathematics/college/6uwqakmkjq6nua21bpopztkrf20jt2flji.png)
Where c is the hypotenuse and a and b are the lengths of the legs.
So, replacing a by 5 and b by 7, we get:
![\begin{gathered} c=\sqrt[]{5^2+7^2} \\ c=\sqrt[]{25+49} \\ c=\sqrt[]{74} \end{gathered}](https://img.qammunity.org/2023/formulas/mathematics/college/l2eubf1xeegerityyg1ntna4ayaec6ey4n.png)
Therefore, the answer is 3. √74