1. **Problem:** Determine the number of triangles that can be created given $\alpha$, $a$, and $b$.
We use the Law of Sines: $$\frac{a}{\sin \alpha} = \frac{b}{\sin \beta}$$
The number of triangles depends on the value of $a$ relative to $b \sin \alpha$ and $b$.
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**1.** $\alpha=110^\circ$, $a=81$, $b=99$
Calculate $b \sin \alpha = 99 \times \sin 110^\circ$.
$$\sin 110^\circ = \sin (180^\circ - 70^\circ) = \sin 70^\circ \approx 0.9397$$
$$b \sin \alpha = 99 \times 0.9397 = 93.03$$
Since $a=81 < 93.03$, and $a < b$, there is **1 triangle**.
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**2.** $\alpha=66^\circ$, $a=73$, $b=71$
Calculate $b \sin \alpha = 71 \times \sin 66^\circ$.
$$\sin 66^\circ \approx 0.9135$$
$$b \sin \alpha = 71 \times 0.9135 = 64.06$$
Since $a=73 > 64.06$ and $a > b$, there is **1 triangle**.
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**3.** $\alpha=135^\circ$, $a=45$, $b=50$
Calculate $b \sin \alpha = 50 \times \sin 135^\circ$.
$$\sin 135^\circ = \sin 45^\circ = 0.7071$$
$$b \sin \alpha = 50 \times 0.7071 = 35.36$$
Since $a=45 > 35.36$ and $a < b$, there is **1 triangle**.
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**4.** $\alpha=60^\circ$, $a=15\sqrt{3}$, $b=30$
Calculate $a$ numerically:
$$15\sqrt{3} = 15 \times 1.732 = 25.98$$
Calculate $b \sin \alpha = 30 \times \sin 60^\circ$.
$$\sin 60^\circ = 0.8660$$
$$b \sin \alpha = 30 \times 0.8660 = 25.98$$
Since $a = b \sin \alpha$, there is **1 right triangle**.
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**Final answers for I:**
1. 1 triangle
2. 1 triangle
3. 1 triangle
4. 1 triangle
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**Slug:** triangle count
**Subject:** trigonometry
Triangle Count A6A0B7
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