1. **State the problem:** Given two congruent triangles $\triangle ABC \cong \triangle FDE$, find the values of $x$ and $y$ given the angles:
- $\angle C = 108^\circ$
- $\angle B = 48^\circ$
- $\angle F = (2x - y)^\circ$
- $\angle D = y^\circ$
2. **Recall the property of congruent triangles:** Corresponding angles of congruent triangles are equal. So,
$$\angle A = \angle F, \quad \angle B = \angle D, \quad \angle C = \angle E.$$
3. **Use the given angles:**
- Since $\angle B = 48^\circ$ and $\angle D = y^\circ$, we have
$$y = 48.$$
4. **Find $\angle A$:** The sum of angles in a triangle is $180^\circ$, so for $\triangle ABC$:
$$\angle A + \angle B + \angle C = 180^\circ$$
$$\angle A + 48 + 108 = 180$$
$$\angle A + 156 = 180$$
$$\angle A = 180 - 156 = 24.$$
5. **Use congruence for $\angle F$:** Since $\angle A = \angle F$,
$$\angle F = 24^\circ.$$
6. **Set up equation for $x$ and $y$:** Given $\angle F = (2x - y)^\circ$, substitute $y=48$ and $\angle F=24$:
$$2x - 48 = 24.$$
7. **Solve for $x$:**
$$2x = 24 + 48 = 72$$
$$x = \frac{\cancel{2}x}{\cancel{2}} = \frac{72}{2} = 36.$$
**Final answers:**
$$x = 36, \quad y = 48.$$
Triangle Angles 7D8F11
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