Respuesta :

When a quadrilateral is inscribed in a circle, the opposite angles are supplementary (they add up to 180 degrees)
x + 6x + 19 = 180
7x + 19 = 180
7x = 161
x = 23

Now substitute 23 for x.

6(23) + 19 = B
B = 157

I really hope this helps you =)