Answer:
10ft/sec
Step-by-step explanation:
In t sec the lady would be at a distance of (speed)(time) = (5 ft/sec)(t sec) = 5t ft.
As the height of the pole is double the height of the lady, from similar triangles, we can deduct the tip of the shadow would be at a distance x = 2 (5t) ft = 10t.
The distance equation is x = 10t ft.
So, the speed is x' = 10 ft/sec.
The speed will be constant like the speed of the lady.