Change the messy words into numerals
3 times a number minus 2 equals 13
3 × n - 2 = 13
3n - 2 = 13
take 2 to the other side
3n - 2 + (2) = 13 + (2)
3n = 15
Divide by 3 on either sides to isolate n
= 
3 and 3 cancels out
n = 5
check:
3 times 5 minus 2 equals 13
3 × 5 - 2 = 13
15 - 2 = 13
13 = 13
The number is 5
3 times a number minus 2 equals 13
3 × n - 2 = 13
3n - 2 = 13
take 2 to the other side
3n - 2 + (2) = 13 + (2)
3n = 15
Divide by 3 on either sides to isolate n
3 and 3 cancels out
n = 5
check:
3 times 5 minus 2 equals 13
3 × 5 - 2 = 13
15 - 2 = 13
13 = 13
The number is 5