Question 1209753
Let's break this problem down step-by-step:

1.  **Define Variables:**
    * Let "x" represent your age.
    * Let "y" represent your brother's age.

2.  **Translate the First Sentence into an Equation:**
    * "My brother is 7 years younger than me."
    * This translates to: y = x - 7

3.  **Translate the Second Sentence into an Equation:**
    * "Twice my age plus 3 times his age is 99."
    * This translates to: 2x + 3y = 99

4.  **Solve the System of Equations:**
    * We have two equations:
        * y = x - 7
        * 2x + 3y = 99
    * Substitute the first equation (y = x - 7) into the second equation:
        * 2x + 3(x - 7) = 99
    * Simplify and solve for x:
        * 2x + 3x - 21 = 99
        * 5x - 21 = 99
        * 5x = 120
        * x = 24

5.  **Solve for y:**
    * Now that you know x = 24, substitute it back into the equation y = x - 7:
        * y = 24 - 7
        * y = 17

**Answer:**

* Your age is 24 years old.
* Your brother's age is 17 years old.