Find the length of the longer diagonal of the rhombus with sides of 6cm and acute angles of 40 degrees.

Question

anonymous · Answer

nvrmind

anonymous · Answer

Umm ok.

anonymous · Answer

I guess what I have to do is divide the rhombus into two triangles. Then what do I do?

anonymous · Answer

And I guess the hypotenuse of one these triangles would be the diaganol I'm looking for correct?

anonymous · Answer

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anonymous · Answer

the length of the longer diagonal is 2y.  since the diagonals of a rhombus are perpendicular and bisect each other we can just focus on 1 triangle.

notice that cos(20 degrees) = y/6.
so y=6*cos(20 degrees).

the length of the longer diagonal is therefore 2y = 2*6cos(20 degrees) = 12*cos(20 degrees)

anonymous · Answer

All in all it was just a brick in the wall...

anonymous · Answer

Haha.

anonymous · Answer

Woah man thanks. That helps. For some reason I thought it would be like this.|dw:1334971083848:dw|