Answer:
-66+12 or -54
Step-by-step explanation:
To remove the parenthesis multiply the number outside of the parenthesis (in this case -6) to the numbers inside of the parenthesis (11, and -2).
A negative multiplied by a positive is a negative.
A negative multiplied by a negative is a positive.
None, a triangle need to have angles measuring 180 degrees , its only possible if the triangle has three angles equaling 60