Ten years ago, a father was twelve times as old as his son and ten years hence, he will be twice as old as his son will be then. Find their present ages.

Explanation

To solve the problem, we will define the present ages of the father and son, set up equations based on the information given, and then solve those equations step by step.

### Step 1: Define Variables
Let:
- \( x \) = Father's present age
- \( y \) = Son's present age

### Step 2: Set Up the First Equation
...