1. **State the problem:** Solve the system of linear equations:
$$x + 2y = 7$$
$$3x - y = 5$$
2. **Formula and method:** We can use substitution or elimination. Here, we'll use elimination.
3. **Step 1: Multiply the first equation by 1 and the second by 2 to align coefficients of $y$:**
$$x + 2y = 7$$
$$6x - 2y = 10$$
4. **Step 2: Add the two equations to eliminate $y$:**
$$x + 2y + 6x - 2y = 7 + 10$$
$$7x = 17$$
5. **Step 3: Solve for $x$:**
$$x = \frac{17}{7}$$
6. **Step 4: Substitute $x$ back into the first equation to find $y$:**
$$\frac{17}{7} + 2y = 7$$
7. **Step 5: Isolate $y$:**
$$2y = 7 - \frac{17}{7}$$
$$2y = \frac{49}{7} - \frac{17}{7} = \frac{32}{7}$$
8. **Step 6: Solve for $y$:**
$$y = \frac{\cancel{2} \times y}{\cancel{2}} = \frac{32}{7 \times 2} = \frac{16}{7}$$
**Final answer:**
$$x = \frac{17}{7}, \quad y = \frac{16}{7}$$
Linear System 087Bdd
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