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
<span>6( 5-8x) +12= -54
30-48x+12=-54 this comes from distributing(multiplying) 6x5 and 6 times -8x
30+12-48x=-54 you have to add the coefficients 30+12
42-48x=-54
-42 -42
-----------------------
-48x=-96 divide by -48
x=2</span>
Answer: the answer is A
Step-by-step explanation: i know this because i am a genius and you should listen to me