Answer:
Step-by-step explanation:
Definition of supplementary
I think it’s the first one because you mirror ABC from the m-axis and then rotate ABC 90 degrees clockwise from point B’ to get to the position of triangle A”B’C”
Answer:
a. Divide the figure into two rectangles, find the area of each rectangle and add them (See the picture attached).
b. 
c. The total area of the figure is 279 square inches.
Step-by-step explanation:
a. Divide the figure into two rectangles (See the picture attached), then find the area of each rectangle and finally, add the areas calculated in order to get the total area of the given figure,
b. The area of a rectangle can be found using this formula:

Where "l" is lenght and "w" is the width.
Area of Rectangle A
You can identify that:

Then, its area is:

Area of Rectangle B
You can identify that:

Then, its area is:

Total area

c. The total area of the figure is 279 square inches.
Answer: The first student is correct
Step-by-step explanation:
If the length of rectangle is x-30=3-z then it must be true that 13 could be one of the answers
9n - 2 - 6n - 3
(9n + -6n) + (-2+-3)
=3n -5