Using the fact that the sum of the interior angles must be 360°, we can see that the value of x is 70°
How to find the value of x?
In a quadrilateral the sum of the interior angles must be 360°. The top interior angle plus 60° must be a plane angle, so we can write:
A + 60° = 180°
A = 180° - 60° = 120°
Now, we can set up an equation for the sum of the four interior angles of the quadrilateral:
130° + 120° + 40° + x = 360°
Solving this for x:
x = 360° - 120° - 130° - 40°
x = 70°