what is 7c-9? im so confused, i need help :(

Answer 1

7c - 9 means

7 times an unknown number minus 9

Answer 2

There is nothing you can say about 7 c - 9 except that it is 7 c - 9

There has to be more to the problem to say anything meaningful.

Answer 3

For example if we said

7 c - 9 = 5

then
7 c = 5+9

7 c = 14

c = 2