Answer:
5z
Step-by-step explanation:
3z+5z-3z(3z gets cancelled)
5z
Step-by-step explanation:

Factors of 39: 1, 3, 13, and 39.
Factors of 65: 1, 5, 13, and 65.
The common factors for 39 and 65 are 1 and 13.
The greatest common factor is 13.
Hi, these equations are pretty easy actually, first thing you should know when working with variables is that you always want to leave the variable alone, let's take the third excersise for example, 12x + 2 = 146. Here you just do the opposite on the other side of the equation depending if the number is positive or negative. Since x is being multiplied by 12 you first get rid of the 2, since its positive you subtract it to 146. Now the answer should be 12x = 144. Now since you're multiplying 12 to x you just divide 12 from 144, 144/12 = 12
x = 12