please explain this. thank you

Answer:
Below
Step-by-step explanation:
We can just plug in 3 for k and solve :
x - 1 / 3 = 3
Step 1. Multiply both sides by 3
x - 1 = 9
Step 2. Move the -1 to the other side and change the sign
x = 9 + 1
x = 10
We can check to see if this works :
10 - 1 / 3 = k
9 / 3 = k
3 = k so this is correct
Hope this helps!