Answer: 15 years ago
Explanation:
- Create an equation using x as Emily's age and x+28 as Nick's age --> 3x=x+28
- Solve the equation by using algebra:
- subtract x from both sides to get 2x=28
- divide both sides by 2 to get x =14
After doing this, we know that Emily's age was 14, so 29-14=15 years ago.
This works because of substitution. These problems are known as age problems and I recommend reading about them since they almost all use the same equations.