Answer:
is the question correct, you end up with no X's
3x -4x + x = 9
or I've got it wrong
45^3 is 45 times 45 times 45. The answer is 91 125.
You multpily the length and the width to find the area of a shape. If the square is 3ft wide, then the square is also 3 ft long if the area is 9.
so, how tall is it?
3 ft. I meant rectangle. Its still the same for the height.
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
