1. **Problem Statement:**
A dragon at point D breathes fire at a target H located 11 cm below its horizontal eye level, with an angle of elevation of 33° from D to H. A human at point J looks up at the dragon at an angle of 40°. We need to find the length of the steam of fire, which is side $j$ (the distance between points H and J).
2. **Understanding the Triangle:**
We have triangle DHJ with angles and sides:
- Angle at D: 33° (angle of elevation of fire)
- Angle at J: 40° (angle human looks up at dragon)
- Vertical drop from D to H: 11 cm (H is 11 cm below D's horizontal line)
3. **Find the third angle at H:**
$$\text{Angle } H = 180^\circ - 33^\circ - 40^\circ = 107^\circ$$
4. **Use the Law of Sines:**
The Law of Sines states:
$$\frac{j}{\sin 33^\circ} = \frac{h}{\sin 107^\circ} = \frac{d}{\sin 40^\circ}$$
5. **Find side $h$ (distance from D to J):**
Since H is 11 cm below D's horizontal line, and angle at D is 33°, the vertical drop relates to side $d$ (opposite angle 40°) and side $w$ (horizontal from D to H). We use the sine of 33° to find $d$:
The vertical drop is opposite to angle 33°, so:
$$11 = d \sin 33^\circ \Rightarrow d = \frac{11}{\sin 33^\circ}$$
6. **Calculate $d$:**
$$d = \frac{11}{\sin 33^\circ} = \frac{11}{0.5446} = 20.2 \text{ cm}$$
7. **Use Law of Sines to find $j$:**
$$\frac{j}{\sin 33^\circ} = \frac{d}{\sin 40^\circ} \Rightarrow j = d \frac{\sin 33^\circ}{\sin 40^\circ}$$
8. **Calculate $j$:**
$$j = 20.2 \times \frac{0.5446}{0.6428} = 20.2 \times 0.8477 = 17.1 \text{ cm}$$
**Final answer:**
The length of the steam of fire $j$ is approximately **17.1 cm**.
Steam Length 408Dc1
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