1. **State the problem:** Solve the system of linear equations:
$$3x + 2y = 12$$
$$-x + 11y = 31$$
2. **Choose a method:** We will use the substitution or elimination method. Here, elimination is convenient.
3. **Eliminate one variable:** Multiply the second equation by 3 to align coefficients of $x$:
$$3(-x + 11y) = 3(31)$$
$$-3x + 33y = 93$$
4. **Add the first and modified second equations:**
$$3x + 2y = 12$$
$$-3x + 33y = 93$$
Adding gives:
$$\cancel{3x} + 2y + \cancel{-3x} + 33y = 12 + 93$$
$$35y = 105$$
5. **Solve for $y$:**
$$y = \frac{105}{35} = 3$$
6. **Substitute $y=3$ into the first equation:**
$$3x + 2(3) = 12$$
$$3x + 6 = 12$$
7. **Solve for $x$:**
$$3x = 12 - 6 = 6$$
$$x = \frac{6}{3} = 2$$
**Final answer:**
$$x = 2, \quad y = 3$$
Linear System 7B1Bbb
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