Diagonal angles have the same measure - not sure what u mean by oposite.
For this case we must resolve the following inequality:

Adding 7 to both sides of the inequality:

Different signs are subtracted and the major sign is placed.

Thus, the solution is given by all the values of "x" less than -5.
The solution set is: (-∞, - 5)
Answer:

See attached image
Answer:
54 students
Step-by-step explanation:
42 / 7 = 6
9 x 6 = 54
42 : 54 = 7 : 9