Question

AB and BC are tangent to circle D. find angle B if arc AEC measures 210 degrees

Answer 1

Angle B = 60°

For explanation look below

Hope this helps!

Answer 2

These are the answers:

Make sure to use the Pythagorean method.
a squared + b squared = c squared

the radius should be 14

Andthis should be the solution

vertices (-10, 3) and (8, 3)
center (-1, 3)
a = 9
b = 2
c = √(9²+2²)
= √85