ANSWER

EXPLANATION
The given problem is

This is defined if and only if

Even the given expression can be simplified to obtain:

The exclusion is

Let the angles be x and (180-x).
Let 2x = 180-x.
Then 3x = 180, and x = 60. One angle is 60 degrees and the other is 180-60, or 120, degrees.
Can you tell us what the expression is in the question?
Answer:
Johnny is wrong.

Step-by-step explanation:
Johnny is wrong.
A better definition would be:
is the set of all elements that belong to at least one A or B.
So, the elements that belong to both A and B, like c and d in this exercise, also belong to
.
So:

Answer:
Step-by-step explanation:
There is no equal sign.
1/2 x - 5*x
is all there is.