A ladder 23 feet long leans against the side of a building, and the angle between the ladder and the building is 25°. (a) Approximate the distance from the bottom of the ladder to the building. (Round your answer to two decimal places.) __ft (b) If the distance from the bottom of the ladder to the building is increased by 2.0 feet, approximately how far does the top of the ladder move down the building? (Round your answer to two decimal places.) __ft
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Yep got that part
oh we should also label the distance from the base of the ladder to the wall lets call it \(x\)
then \[\cos(25)=\frac{x}{23}\] an so \[x=23\cos(25)\] and a calculator
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22.797
since for right triangles, cosine is "adjacent over hypotenuse"
yeah so it would be 22.80 ??
feet
that is not what i get
what did you get?
not sure why our answers should be different when i am on a computer i always use wolfram
Weird, neither of those are right. My homework offers unlimited trys
how many decimal places does it want?
two
ooooh damn! i should learn to read lets try again
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says the angle with the BUILDING not the ground
in this case \[\sin(25)=\frac{x}{23}\] making your answer \[x=23\sin(25)\]
YEAH! i had it drawn that exact same way and i just figured i was wrong and you were right haha cause you looked smart. Pshh i should trust myself.
oh yeah i am not very smart, especially at reading
yep that's correct
so then for B) it would be 11.72
i don't know lets see if we can do this without me screwing up the distance we know was \(9.72\) and now it is \(11.72\) but it is not asking for you to add 2 to the distance of the bottom of the ladder from the building, but now it is asking for the decrease in the height of the ladder
you can now find the distance from the bottom of the building to the top of the ladder by pythagoras, since you have two sides of a right triangle, the hypotenuse \(23\) and the base of the triangle \(11.72\)
so you need two numbers, the original height of the ladder, which was \[\sqrt{23^2-9.72^2}\] and the new height \[\sqrt{23^2-11.72^2}\]
subtract the second from the first to see how far down it moved
wonder if i messed that one up too?
no that looks right
I got 19.7899
soo 19.79
http://www.wolframalpha.com/input/?i=sqrt%2823^2-9.72^2%29-sqrt {23^2-11.72^2%29
can't have moved down as far as you said now sure my answer is right, but positive it is not 19.79
oh you have to copy and paste the link i sent it wont open as it is
wont let me copy it
what did you get?
try this http://www.wolframalpha.com/input/?i=sqrt%2823^2-9.72^2%29-sqrt%2823^2-11.72^2%29
seems more reasonable bottom increases by 2, top decreases by \(1.06\)
Okay that was right! i get it now, wow i was way off
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oh it was right? guess i redeemed myself for the first dumb error
Yep, thank you very much! i owe you big time
Would you be able to help me with another problem? if you have time?
@satellite73
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