I this identity property of addition or additive inverse property?

9x + (-9x) + 12=0+12

I see both of the properties but I'm not sure ...

There are 11 books on a shelf 3 of these books are new what is the ratio of used books to new books

Given that y varies directly with x, find the constant of variation (k) and write a function that models each situation. 1. (3,6)

How many integers are greater than 9 37 and less than 37 9

7x-21. x2-5x+6 5x + 6 x+12

Happy days child center employs six teachers to care for 36 students what is the student to teacher ratio at happy days

A high school has a total of 850 students. there are 60 more females students than male students. a. write a system of linear equations that represents this situation. b. how many students are female? male?

There are 6 chocolate, 4 strawberry. and 5 vanilla ice. what is the probability that an ice cream chosen at random is a chocolate flavor

The height h (in feet) above the water of a cliff diver is modeled by h=-16t2+8t+80, where t is the time (in seconds). How long is the diver in the air?

A snail travels 3 feet in one hour. In each subsequent hour, the snail travels three-fourths the distance it traveled in the previous hour. How far does the snail travel in 6 hours

A right triangle has legs that are 19 in. and 23 in. What is the area of the triangle