Angle 2 and angle 4 are vertical angles which makes them congruent
Answer:
Complementary angles.
Step-by-step explanation:
Notice that
and
, by given.
, by sum of angles.
, by supplementary angles definition.

Which means,

Therefore,
, in other words, angles a and b are complementary by definition.
Answer:
5 classes - 2 bass classes and 3 viola classes.
Step-by-step explanation:
Find the greatest common factor (GCF)
List the factors of 20 and 30:
20: 1, 2, 4, 5, 10, 20
30: 1, 2, 3, 5, 6, 10, 15, 30
The greatest factor that both numbers share is 10.
Therefore, there are 10 students in each class. So, she teaches 2 bass classes and 3 violas classes.
hope this helps! <3
Answer:
1
Because 9/3= 3
And 3-2=1
Hence the answer is 1
Step-by-step explanation: