Mike is using a telescope to view three stars. He notes the distances and angles between the lines joining the stars, as shown below.
Which expression shows the distance between Star 2 and Star 3?

Question

Mike is using a telescope to view three stars. He notes the distances and angles between the lines joining the stars, as shown below. 
Which expression shows the distance between Star 2 and Star 3?

anonymous · Answer

A)  y sec x° 

B)  y over sec x° 

C)  y cot x° 

D) y cot over x°

anonymous · Answer

cosx = y/d, where d is the distance you want...

but this can also be written as secx = d/y

and if you solve for d in that second equation, you'll have your answer... :)

anonymous · Answer

could you like step by step explain it

anonymous · Answer

sure... do you agree that in the right triangle in the picture, cosx = y/d  ?

anonymous · Answer

yea

anonymous · Answer

ok... secx = 1/cosx,  do you agree with this?  it is a basic identity....

anonymous · Answer

one sec

anonymous · Answer

another way to say that ^^ is cosx = 1/secx

anonymous · Answer

okay

anonymous · Answer

ok so...

anonymous · Answer

wait on the cosx thing why is the x there?

anonymous · Answer

x is the angle...

anonymous · Answer

ok i think i got it but it will take a min

anonymous · Answer

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