The correct answer are A. and B.
Good luck!!!
Answer:
see explanation
Step-by-step explanation:
Using the double angle identity for sine
sin2x = 2sinxcosx
Consider left side
cos20°cos40°cos80°
=
(2sin20°cos20°)cos40°cos80°
=
(2sin40°cos40°)cos80°
=
(sin80°cos80° )
=
(2sin80°cos80° )
=
. sin160°
=
. sin(180 - 20)°
=
. sin20°
=
= right side , thus proven
All the triangles are similar, so the ratio of (long leg)/(short leg) is the same. The long leg of ΔADB is
.. AD = AC -DC = 20 -4
.. AD = 16
Then
.. (long leg)/(short leg) = AD/DB = BD/DC
.. 16/h = h/4
.. h^2 = 64
.. h = 8
Selection D is appropriate.
_____
You may see this again. The altitude (h) from the right angle in a right triangle is the geometric mean of segments AD and DC. That is,
.. h = √((AD)*(DC))
Answer:
6/5
Step-by-step explanation:
Answer:
26:26
Step-by-step explanation:
I hope I've helped :)