Answer:
The third exterior angle is 
Step-by-step explanation:
Given


Required
The third exterior angle 
The exterior angles of a triangle add up to 360 degrees.
So:

Make
the subject

Substitute known values


Answer: She added 7x and 3y
Step-by-step explanation: The final answer should be 7x + 3y, not 10xy.
Answer:
Assciates Property
Step-by-step explanation:
look at the picture above
Answer:
1 1/4
Step-by-step explanation:
3 1/8 - 1 7/8
I like to line them up vertically
3 1/8
- 1 7/8
---------------
We need to borrow from the 3
Take 1 from the 3 and make it 8/8
2 (1/8+8/8)
- 1 (7/8)
---------------------
2 (9/8)
- 1 (7/8)
---------------------
1 2/8
Simplify the fraction by dividing by 2 on the top and bottom
1 1/4