Answer:

Step-by-step explanation:
Using the addition formulae for cosine
cos(x ± y) = cosxcosy ∓ sinxsiny
---------------------------------------------------------------
cos(120 + x) = cos120cosx - sin120sinx
= - cos60cosx - sin60sinx
= -
cosx -
sinx
squaring to obtain cos² (120 + x)
=
cos²x +
sinxcosx +
sin²x
--------------------------------------------------------------------
cos(120 - x) = cos120cosx + sin120sinx
= -cos60cosx + sin60sinx
= -
cosx +
sinx
squaring to obtain cos²(120 - x)
=
cos²x -
sinxcosx +
sin²x
--------------------------------------------------------------------------
Putting it all together
cos²x +
cos²x +
sinxcosx +
sin²x +
cos²x -
sinxcosx +
sin²x
= cos²x +
cos²x +
sin²x
=
cos²x +
sin²x
=
(cos²x + sin²x) = 
It's 2.7 pounds because I set up a proportion of 150 over 90 = 4.5 over X and multiplied 90 * 4.5 divided by 150
Answer:
(1) Area of second triangle= 50 cm^2.
(2) Area of ΔABC=98 cm^2.
and Area of ΔDFG=175 cm^2.
Step-by-step explanation:
<em>" For two similar triangles the ratio of sides is equal to the ratio of square of their areas".</em>
i.e. if a,b are the corresponding sides of two similar triangles and let A and B denote the area of two triangles then we have the relation as:

(1)
for the first question:
we have a=2, b=5.
A=8 cm^2.
Hence,

B=50 cm^2.
Hence, the area of second triangle is 50 cm^2.
(2)
In second option we have:
a=6 and b=5.
A-B=77 cm^2.
A=77+B

Hence area of second triangle i.e. ΔDFG is 175 cm^2.
and area of first triangle i.e. ΔABC=175-77=98 cm^2.
Answer:
180 hours
Step-by-step explanation:
Surfer #1 takes a capsule every 6 hours, but this is also equal to 2 capsules every 12 hours. Surfer #2 takes 1 capsule every 12 hours. Thus, both surfers take a total of 3 capsules every 12 hours.
By dividing 45 total capsules they need to consume by 3, the number of capsules the surfers consume every 12 hour, you get the total number of hours times 12 it takes for them to consume 45 capsules. 45 / 3 = 15, so it takes 15 * 12 hours for them to consume 45 capsules. This is equal to 180 total hours.
Answer:
y=−2x+4
Step-by-step:
2y+4x=8
Step 1: Add -4x to both sides.
4x+2y+−4x=8+−4x
2y=−4x+8
Step 2: Divide both sides by 2.
2y
/2
=
−4x+8
/2
y=−2x+4