Answer:
58 units squared
Explanation:
**I'm doing the question with the 7 by 3 triangle in the picture, not 777 by 333**
Pythagorean Theorem:
, where c is the length of the hypotenuse.
The given sides are legs, therefore,
![3^2+7^2=c^2](https://img.qammunity.org/2022/formulas/mathematics/high-school/svndk640rfyl75w9yft3yyogdbx94v06si.png)
![9+49=c^2; 58=c^2; c=√(58)](https://img.qammunity.org/2022/formulas/mathematics/high-school/9ky7p79y4sakdzsct69mzmrsml3egx76zc.png)
c is also one of the sides of the square. A square's area is one of the sides' lengths squared, so:
![(√(58)) ^(2)=58](https://img.qammunity.org/2022/formulas/mathematics/high-school/urklhvx7weadpg4zx64frcta515n9lkx7u.png)