Asked by Tia
A smokestack is 150
feet high. A guy wire must be fastened to the stack
40
feet from the top. The guy wire makes an angle of 40∘
with the ground. Find the length of the guy wire rounded to the nearest foot.
- I've got no idea where to start or what to do. I understand that it is 150 high, but do we add on the other 40 to that? It seems that there are two equations going on, overall I am just very confused. Please and thank you for any help.
feet high. A guy wire must be fastened to the stack
40
feet from the top. The guy wire makes an angle of 40∘
with the ground. Find the length of the guy wire rounded to the nearest foot.
- I've got no idea where to start or what to do. I understand that it is 150 high, but do we add on the other 40 to that? It seems that there are two equations going on, overall I am just very confused. Please and thank you for any help.
Answers
Answered by
scott
this is trig
the wire is fastened 40 feet BELOW the top ... how high up?
the wire is the hypotenuse of a right triangle
... you know the length of one side (height of attachment point)
... you know the angle with the ground
draw a sketch
the wire is fastened 40 feet BELOW the top ... how high up?
the wire is the hypotenuse of a right triangle
... you know the length of one side (height of attachment point)
... you know the angle with the ground
draw a sketch
Answered by
Reiny
Read carefully, the wire is attached 40 ft from the top, so the wire is attached 110 ft above the ground.
So now it becomes very simple, a right-angled triangle with base angle of 40°, and an opposite side of 110 ft.
We want the hypotenuse h, so
sin40° = 110/h
solve for h, see how easy it becomes ?
(let me know what you get)
So now it becomes very simple, a right-angled triangle with base angle of 40°, and an opposite side of 110 ft.
We want the hypotenuse h, so
sin40° = 110/h
solve for h, see how easy it becomes ?
(let me know what you get)