Fill in the blank. In the triangle below, y=__. Round your answer to two decimal places. Please explain, thank you.
What side of the triangle is Y ?
did you see the attachment
Yes i m asking you like the name of the side
|dw:1413736128032:dw|
oh ok so hypotenuse then
Yup! Okay now we use the Pythagorean theorem
a^2+b^2=c^2
so do we fill in the information we already have into this formula
i think i made a mistake . We dont use the theorem we use Sine
Do you have a calculator ?
yes
|dw:1413736596952:dw|
We know one angle measure beside 90 . That angle is 52
So type 52 then hit sine
sin(52) = 0.788010754
I got 0.98662759204
oh ok im not sure why i got that i pressed sin(52) and got 0.788
I think your right though
yeah i checked online it is
Yup i tried it on another calculator your right :)
Sine = opposite / hypotenuse
Plug our values into that
the opposite is 35 but the hypotenuse is y on the picture
0.788010754 = 35/y
im still confused about the y part what is y?
In your picture the hyotenuse was labeled Y
yeah but on the formula Sine = opposite / hypotenuse or 0.788010754 = 35/y don't you need to plug in something for y to solve
We dont have the value of y . Were using that equation to find the value of y
oh ok
So now what do you get ?
y=35/sin(38°)=56.85
Where did sin 38 come from
the 38 degrees is a result of 180°-52-90=38 being that a triangle is 180 degrees I subtracted 52 and 90
You dont do sine again . Just do regular algebra to find y in the equation 0.788010754 = 35/y
I got 44.42
@dumbcow @jim_thompson5910 Could you check this please ?
http://cossincalc.com/#angle_a=&side_a=35&angle_b=90&side_b=&angle_c=52&side_c=&angle_unit=degree
hmm i think you should have used cos instead of sin the 35 is adjacent to angle 52
I just right now found that website above
or do what @KJ4UTS did and use angle 38 :)
\[\sin 38 = \cos 52 = \frac{35}{y}\] \[y = \frac{35}{\sin 38} = \frac{35}{\cos 52}\]
i got 56.84942359 for both and if it says round two decimal places I guess that makes the answer 56.85 i think?
Yes rounded its 56.85
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