Bearing R From P
1. **Problem statement:**
We have three points: P, Q, and R. Q is 60 km due north of P, and R is 45 km due east of Q. We need to find the bearing of R from P.
2. **Understanding bearings:**
Bearing is the direction measured clockwise from the north line. It is expressed in degrees from 0° to 360°.
3. **Set up the coordinate system:**
Place P at the origin $(0,0)$.
Since Q is 60 km north of P, Q is at $(0,60)$.
Since R is 45 km east of Q, R is at $(45,60)$.
4. **Find the vector from P to R:**
The vector PR has coordinates $(45 - 0, 60 - 0) = (45, 60)$.
5. **Calculate the bearing:**
The bearing angle $\theta$ is measured clockwise from north.
First, find the angle $\alpha$ between vector PR and the north direction (positive y-axis).
Using the tangent function:
$$\tan(\alpha) = \frac{\text{east displacement}}{\text{north displacement}} = \frac{45}{60} = 0.75$$
Calculate $\alpha$:
$$\alpha = \arctan(0.75) \approx 36.87^\circ$$
6. **Determine the bearing:**
Since the vector is east of north, the bearing from P to R is:
$$\text{Bearing} = 0^\circ + 36.87^\circ = 36.87^\circ$$
**Final answer:**
The bearing of R from P is approximately $36.87^\circ$ measured clockwise from north.