Answer is 10.5 miles
I used Pythagorean theory to solve for the unknown distance from the waterfall to lookout point.
a^2 + b^2 = c^2
2^2 + 4^2 = c^2
20 = c^2
Take square root of both sides
4.47 = c
Rounded to 4.5 miles
Add 4 miles and 2 miles and 4.5 miles
10.5 miles total
I used Pythagorean theory to solve for the unknown distance from the waterfall to lookout point.
a^2 + b^2 = c^2
2^2 + 4^2 = c^2
20 = c^2
Take square root of both sides
4.47 = c
Rounded to 4.5 miles
Add 4 miles and 2 miles and 4.5 miles
10.5 miles total