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

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