Question

Is (6,-10) a solution of y=3x-8

Answer 1

You can easily test this if you know that (6, -10) corresponds to (X, Y). Knowing this, you can: 

X = 6
Y = -10

you put this into your equation:

-10 = 3*6 - 8

calculate it:

-10 = 18 - 8
-10 = 10
This is not true of course, -10 is not equal to 10. Therefore, (6, -10) is not a solution of y = 3x-8 :)