Question

Find angle A if DE is equal to 66 degrees and BC is equal to 23 degrees.

Answer 1

But how do I solve for A?

Answer 2

sorry, the angle DCE is 33°, CDB is 23°/2, show the triangle ACD

Answer 3

the relation, DCE (external) is CDB + A

Answer 4

use this formula :-
|AE| |CE|=|AD| |BD|

Answer 5

angle A is 1/2 the difference between the two intercepted arcs.
in other words
\[ \angle A= \frac{1}{2}( \widehat{DE}- \widehat{BC})\]

Answer 6

A=4?