Can someone please give me the answers to the following math questions and tell how you got the answer?

Question

y=6x+3

p=12-7z

3n+r=15

2d+3m=6

Answer 1

1.  y=6x+3 is a linear equation. Meaning you can use substitution. Any number you put in X you will get Y. ex. x=1 y= 9

the rest are the same. just use small number like 0,1,-1

      hope this helps

Answer 2

These aren't questions, they are just equations.  Are there directions about what you are supposed to do with them?