Answer: From the 60° angle, the flagpole is the opposite side and the shadow is the adjacent side of the triangle.
tangent 60° = opposite/adjacent
so
tan 60° = 20/x
multiply both sides by x and you have
x · tan60° = 20
divide both sides by tan 60° and you have
x = 20/tan60°
x = 11.5 ft.
if this is wrong sorry don’t be mad but if it’s right then hope this helps
1,000,000,000 standard form
one billion word form
X = velocity of plane
y = velocity of wind
x - y = 1680/5 = 336 mph .....(1) [ plane flying against the wind]
&
x + y = 1680/4 = 420 mph....(2) [ plane flying with the wind]
Adding (1) and (2) to eliminate y gives
2x = 756
x = 378 mph is the speed of the plane with no wind.