trapezium, how to calculate angles?

Settings
- LaTeX
  Compiler
  
  Auto-Completion
  
  Auto-Compilation
  
  Center MathJax
  
  UX
  
  Design
  
  Font size
Code Search

1
2
····\documentclass[12pt,tikz,border=3mm]{standalone}¬
····%····\usepackage{zfc-book-standalone}¬
XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX

LaTeX

?	Show / hide this help menu
ctrl + space
ctrl + s
ctrl + e

Keyboard Shortcuts: