How to find the missing angle of this quadrilateral if the other angles are 108 degrees, 99 degrees, and 78 degrees?

Question

asked Dec 18, 2018 230k views

1 Answer

Kerrine · Answer 1 · 2018-12-24T18:19:12+0000

alll angles in a quadrilateral add to 360

so
missing angle=x
108+99+78+x=360
285+x=360
minus 285 from both sides
x=75

missing angle is 75 degrees