1. **State the problem:** We are given angles at point R with expressions $(12x - 4)^\circ$, $(4y)^\circ$, $(5y)^\circ$, and a right angle of $90^\circ$. We need to find the values of $x$ and $y$.
2. **Use the angle sum rule:** The angles around point R form a full circle, so their sum is $360^\circ$.
3. **Write the equation:**
$$ (12x - 4) + 4y + 5y + 90 = 360 $$
4. **Simplify the equation:**
$$ 12x - 4 + 9y + 90 = 360 $$
$$ 12x + 9y + 86 = 360 $$
5. **Isolate terms:**
$$ 12x + 9y = 360 - 86 $$
$$ 12x + 9y = 274 $$
6. **Simplify by dividing by common factor 1 (no change):**
$$ \cancel{12}x + \cancel{9}y = 274 $$
7. **Use the right angle to find a relation between $x$ and $y$:**
Since the right angle is $90^\circ$, and the angles $(4y)^\circ$ and $(5y)^\circ$ are adjacent to it, their sum plus $90$ must be $180^\circ$ (straight line):
$$ 4y + 5y + 90 = 180 $$
$$ 9y + 90 = 180 $$
$$ 9y = 90 $$
$$ y = 10 $$
8. **Substitute $y=10$ into the first equation:**
$$ 12x + 9(10) = 274 $$
$$ 12x + 90 = 274 $$
$$ 12x = 274 - 90 $$
$$ 12x = 184 $$
$$ x = \frac{184}{12} $$
9. **Simplify fraction:**
$$ x = \frac{\cancel{184}^{\times 1}}{\cancel{12}^{\times 1}} = \frac{184}{12} = \frac{46}{3} \approx 15.33 $$
**Final answers:**
$$ x = \frac{46}{3} $$
$$ y = 10 $$
Angle Values 048371
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