Asking Your Mother to Let You Shave?

My mom won't let me shave my legs and facial hair. It is normal for a girl to shave at my age, but when I ask her about it she gets mad and starts to scold me. Sometimes I'm just too afraid to ask her. She even says that if I did it she'll kill me and stuff. The last time I asked her was like 4 months ago. I'm really ashamed of showing off my face because my my moustache, they even make fun of me at school. But I am still really scared to ask my mom.

Any advice?