∠a and ∠b are complementary angles ∠a measures 59 degrees what is the measure of ∠b

Definition: Complementary angles add up to 90 degrees (they form a right angle)

A+B = 90
59+B = 90 replace angle A with 59
B+59 = 90
B+59-59 = 90-59 subtract 59 from both sides
B+0 = 31
B = 31

The measure of angle B is 31 degrees

No a triangle cannot be formed because when you add the two smallest number together (which would be 11) the have to be bigger than the number it is "against" ( which would be 12)