1. **State the problem:**
Find the sum of the vectors $\langle 7, -2 \rangle$ and $\langle 1, 8 \rangle$, then find the magnitude and direction of the resultant vector.
2. **Add the vectors:**
$$\langle 7, -2 \rangle + \langle 1, 8 \rangle = \langle 7+1, -2+8 \rangle = \langle 8, 6 \rangle$$
3. **Find the magnitude of the resultant vector:**
The magnitude formula is $$|\mathbf{v}| = \sqrt{x^2 + y^2}$$
So,
$$|\langle 8, 6 \rangle| = \sqrt{8^2 + 6^2} = \sqrt{64 + 36} = \sqrt{100} = 10$$
4. **Find the direction (angle) of the resultant vector:**
The direction $\theta$ is given by
$$\theta = \tan^{-1}\left(\frac{y}{x}\right) = \tan^{-1}\left(\frac{6}{8}\right)$$
Calculate:
$$\theta = \tan^{-1}(0.75) \approx 36.87^\circ$$
Rounded to the nearest degree:
$$\theta \approx 37^\circ$$
5. **Interpretation:**
The resultant vector has magnitude 10 and points at an angle of $37^\circ$ above the positive x-axis (east direction).
**Final answer:**
- Sum vector: $\langle 8, 6 \rangle$
- Magnitude: 10
- Direction: $37^\circ$
Vector Sum 5017E7
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