Answer:
x = 20
Explanation:
→You can use the Pythagorean Theorem to solve this:
![a^2 +b^2=c^2](https://img.qammunity.org/2021/formulas/mathematics/high-school/gd371mve3r2wxllkte1z5d36ebe5a8t4lf.png)
→The "a," and "b," are the legs, 21 and x, while the "c," is the hypotenuse, 29. In this case, we are trying to find the value of a leg:
![21^2+b^2=29^2](https://img.qammunity.org/2021/formulas/mathematics/middle-school/3geslafawzie1aqm50df74ij3gelg8v3it.png)
![441+b^2=841](https://img.qammunity.org/2021/formulas/mathematics/middle-school/v1mm2uo6x0rj52nbljqywkhg1heyxjqxiu.png)
→Subtract 441 from both sides:
![b^2=400](https://img.qammunity.org/2021/formulas/mathematics/middle-school/6388q9zz87hy7qz87c7ylzdtmdms27j5se.png)
→To get "b," by itself, you must take the square root of both sides, like so:
![√(b^2) =√(400)](https://img.qammunity.org/2021/formulas/mathematics/middle-school/6km3z274oeg3wwfmly7tphzpkm5vwh85rt.png)
![b = 20](https://img.qammunity.org/2021/formulas/mathematics/middle-school/uvka4dkjmuezixyfx7iq2ed21aahbd0bsb.png)