Answer:
x = 91
Explanation:
The sum of the 4 interior angles of a quadrilateral = 360°
Sum the 4 angles and equate to 360, that is
x + 10 + x - 10 + x + 6 + x - 10 = 360 , then
4x - 4 = 360 ( add 4 to both sides )
4x = 364 ( divide both sides by 4 )
x = 91