Answer : The length of BC in the right triangle is, 75
Step-by-step explanation :
Using Pythagoras theorem in ΔBAC :
![(Hypotenuse)^2=(Perpendicular)^2+(Base)^2](https://img.qammunity.org/2020/formulas/mathematics/high-school/nuhyb0teqpx65r7s5ri7yj0t4wqlnrvj8l.png)
![(BC)^2=(AB)^2+(AC)^2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/i9w0yg9xr9oxkjak8ohyloimk6kwa6r9lp.png)
Given:
Side AB = 21
Side AC = 72
Now put all the values in the above expression, we get the value of side BC.
![(BC)^2=(21)^2+(72)^2](https://img.qammunity.org/2020/formulas/mathematics/middle-school/em5uuw6gbh136rrue0sw3d1v35qmoib39z.png)
![BC=√((21)^2+(72)^2)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/7tdj56y95ai12vnnut0h871stuhsbl0khm.png)
![BC=√(441+5184)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/ijb9762o0xgji8mk5y656jyv5s84lvvr5l.png)
![BC=√(5625)](https://img.qammunity.org/2020/formulas/mathematics/middle-school/nfdz3gxo93gckfnqbpzsqj3ngqnpywwjlk.png)
![BC=75](https://img.qammunity.org/2020/formulas/mathematics/middle-school/odkkf2k5butyxxgxsuwea8e640vxo8ta2r.png)
Therefore, the length of BC in the right triangle is, 75