Answer
The speed of the wind $u$ is 11.3 mph. The wind is blowing toward the northwest direction at a bearing of $315^{\circ}$.
Work Step by Step
$u = -8~i+8~j$
The speed of the wind is the magnitude of the vector $u$. We can find the magnitude of the vector $u$:
$\vert u \vert = \sqrt{(-8)^2+8^2}$
$\vert u \vert = 11.3$
The wind is blowing toward the northwest. Since the horizontal component is equal in magnitude to the vertical component, the wind is blowing at a bearing of $270^{\circ}+45^{\circ} = 315^{\circ}$.
The speed of the wind $u$ is 11.3 mph. The wind is blowing toward the northwest direction at a bearing of $315^{\circ}$.