a 20 foot ladder rests against a building 15 feet from the floor. how far does the ladder extend from the base of the wall? what angle does the ladder make with the ground?
I believe this is the scenario |dw:1408730557448:dw|, yes?
yes that's what i drew . i'm not sure how to get the angle from there
you could take the arc sine of 3/4
where did you get 3/4 from ?
first off that is wrong, so nvm secondly, unless i am miss my guess the picture is wrong too!
how ? the 20ft is the ladder and the 15ft is the wall .
oh maybe not fifteen feet from the floor might mean the height of the ladder
ok fine lets say that is right then \[\sin(a)=\frac{15}{20}=\frac{3}{4}\] so \[a=\arcsin (\frac{3}{4})\]
wow okay that makes sense . if the picture was wrong what would you do ?
now i think it is right but if it is wrong and the 15 is along the ground, take the arc cosine
we say that: \[\sin a=15/20 \\ \sin a =3/4 \\a=\sin^{-1}(3/4) \\ a\approx 48.6 degrees\]
\[x=20 \cos \left(\sin ^{-1}\left(\frac{15}{20}\right)\right)=5 \sqrt{7}=13.2288 \]
which is right ?? you all have different answers ...
The length of the unknown triangle side is:\[\sqrt{20^2-15^2}=5 \sqrt{7}=13.2288 \]The angle is:\[\frac{180 \sin ^{-1}\left(\frac{15}{20}\right)}{\pi }=48.5904 \text{ degrees} \]
what is the length of the third side ?
i doubt its a decimal but i could be wrong
never mind its right
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