i'm retarded at math

[l a c e y]

WHAT THE FUCK HELP.

okay so this is the little write up and picture on the page i have to complete and idk what to fuckin do on this thing.

two points, A and B, are on the same side of a tower in the same vertical plane as the tower. the angle of elevation of the top of the tower from point A is 28 degrees. point B is closer to the tower, 140 m from point A. the angle of elevation of the top of the tower from point B is 37 degrees. determine the height of the tower.

and it also says the answer should be 250 m.

[Socks]

Math is not the issue.

[l a c e y]

yes it is.
i am good at every other subject except math.

[Ezloﺕ]

wait is AB 140 m?

[l a c e y]

um yeah a to b is 140 m

[Daddy]

Well, the top angle from A is 62Ã,º
From B the top is 53Ã,º
im too lazy

[[REDACTED]]

What do they want you to use? Right-triangle trig, or solve using the law of sines?

[russell]

inscribe another right triangle in there by putting a vertical line from point B straight up.

tan28 = x/140

this gives you the length of the line you just made

now flip this right triangle horizontally so the hypotenuse is going from the master triangle's right angle to the master triangle's hypotenuse. use the side length you just got to do

tan45 = (side length you got) / x

this time x is the distance from B to the end.

Finally, use this distance with the original inner triangle:

cos37 = (distance from B to end) / x

And this x should be the final answer.


there's probably a much easier way to do it

[russell]

oh yeah I think law of sines can be used to do it simply but I did with basic trig functions. 

[l a c e y]

inscribe another right triangle in there by putting a vertical line from point B straight up.

tan28 = x/140

this gives you the length of the line you just made

now flip this right triangle horizontally so the hypotenuse is going from the master triangle's right angle to the master triangle's hypotenuse. use the side length you just got to do

tan45 = (side length you got) / x

this time x is the distance from B to the end.

Finally, use this distance with the original inner triangle:

cos37 = (distance from B to end) / x

And this x should be the final answer.


there's probably a much easier way to do it

kay what does that bolded part mean?
also where is tan 45 cokming from..

[Dullahan]

Here is how you do this, because my math was a little more advance than yours.

I'm gonna call the top corner D, and the corner with the right angle C.

You'll need to find out every angle in triangle ABD. First, use the line theorem to figure out angle B by subtracting 37 from 180. Should give you 143 degrees. Now since all triangle angles add up to 180 degrees, all you need to do is subtract 28 and 143 from 180, giving you 9 degrees. You now need to use the sine law to figure out line BD. To do this, use the sine law (140/sin9 = a/sin28). Call that answer x.

Now that you have x, use the sine law to figure out ?. (?/sin37 = x/sin90)

[russell]

kay what does that bolded part mean?
also where is tan 45 cokming from..

because the hypotenuse of the smaller triangle you made up is bisecting the right angle of the larger triangle

law of sines is easier, do it that way

[Kalahari Inkantation]

Start by filling in all of the other angles you can find out. The obtuse angle adjacent to 37 degrees is 143 degrees because they're supplementary and together add up to 180 degrees. 143+28 is 171, and a triangle can only be 180 degrees. So subtract 180 from 171 and you get 9 degrees, which is the measure of the last angle.
And of course, the right angle is 90 degrees.



Then, use Law of Sines to find the measure of side A, the line dividing the triangles in two, which is across from angle A.
First, set up the fraction. Start with 140/sin9, since the side that measures 140 meters is across from the angle that measures 9 degrees. Let's say the line dividing the triangle in 2 is line X. If 140/sin9=X/sin28, what is X?



Cross multiply and divide, and you should get X=420.



Now that you have that number, you can find the measurements of the other side of the triangle by doing just about the same thing you did before, but with different numbers.

Once again, use the Law of Sines to find the height of the tower.



Cross multiply and divide, and there's your answer. It's around 250m, depending on how you rounded.

[Kalahari Inkantation]

Oh, screw you all.

[l a c e y]

alrighty i'm done.
thanks everrryonee.