1. **State the problem:** We have pairs of right triangles with angles labeled as $(y + 4)^\circ$ and $(2y - 15)^\circ$ and sides involving expressions with $x$. We want to find the values of $x$ and $y$ that satisfy the angle relationships.
2. **Use the angle sum property of triangles:** The sum of angles in any triangle is $180^\circ$. Since these are right triangles, one angle is $90^\circ$. Therefore, the other two angles must sum to $90^\circ$:
$$ (y + 4) + (2y - 15) = 90 $$
3. **Simplify the equation:**
$$ y + 4 + 2y - 15 = 90 $$
$$ 3y - 11 = 90 $$
4. **Solve for $y$:**
$$ 3y = 90 + 11 $$
$$ 3y = 101 $$
$$ y = \frac{101}{3} $$
5. **Calculate $y$ value:**
$$ y = 33.666\ldots \approx 33.67 $$
6. **Use trigonometric ratios to find $x$:** For the triangle with sides 12 (vertical) and 5 (horizontal), and angle $(y + 4)^\circ$, use tangent:
$$ \tan(y + 4) = \frac{\text{opposite}}{\text{adjacent}} = \frac{12}{5} $$
7. **Calculate $\tan(y + 4)$:**
$$ y + 4 = 33.67 + 4 = 37.67^\circ $$
$$ \tan(37.67^\circ) \approx 0.77 $$
8. **Check consistency:** Since $\frac{12}{5} = 2.4$, and $\tan(37.67^\circ) \approx 0.77$, this suggests the angle labeling or side assignment might differ. Instead, use the other angle $(2y - 15)^\circ$ and side expressions to find $x$.
9. **Use the right triangle with horizontal side $(2x - 3)$ and angle $(2y - 15)^\circ$:**
Since the vertical side is 12, use tangent:
$$ \tan(2y - 15) = \frac{12}{2x - 3} $$
10. **Calculate $2y - 15$:**
$$ 2y - 15 = 2 \times 33.67 - 15 = 67.34 - 15 = 52.34^\circ $$
11. **Calculate $\tan(52.34^\circ)$:**
$$ \tan(52.34^\circ) \approx 1.28 $$
12. **Set up equation and solve for $x$:**
$$ 1.28 = \frac{12}{2x - 3} $$
Multiply both sides by $2x - 3$:
$$ 1.28(2x - 3) = 12 $$
$$ 2.56x - 3.84 = 12 $$
Add $3.84$ to both sides:
$$ 2.56x = 15.84 $$
Divide both sides by $2.56$:
$$ x = \frac{15.84}{2.56} $$
13. **Calculate $x$ value:**
$$ x = 6.1875 $$
**Final answers:**
$$ y = \frac{101}{3} \approx 33.67 $$
$$ x = 6.19 $$
Triangle Angles 9A449B
Step-by-step solutions with LaTeX - clean, fast, and student-friendly.