need some help please!
I don't know how to do this.
![need some help pleaseI dont know how to do this class=](https://us-static.z-dn.net/files/d80/bba88b4e9db750db947aca29aa56f26b.jpg)
Check the picture below.
bearing in mind that twin sides stemming from a common vertex, will make twin angles at the base, thus 74° has a twin.