Answer:
6
Step-by-step explanation:
sets cannot have repeated elements. So this set only has the letters B, A, L, D, E, R which means the cardinality is 6
50
Step-by-step explanation:
Since AE is the bisector of angle BAC,so angle BAE and Angle CAE is equal. Here Angle CAE and Angle EAC is same.
therefore,
m(Angle BAE)=m(Angle EAC)

or, 2x=40
or, x=20
Hence,
m(Angle EAC)=

=

The answer: x is equal to 50