Twelve more than the product of a number and 5 is 52

Let the unknown number be y.

We can list the equation out by the clues given.

5y + 12 = 52

Then solve this as simple algebra!

Shift + 12 to the other side and be - 12

5y = 52-12

5y = 40

Shift x5 to the other side and be : 5

y = 40 / 5

y = 8

Therfore the unknown number is 8.