Answer:
a) 
b)

c)

d)
cos 330° = 1- 2 sin² (165°)
Step-by-step explanation:
<u><em>Step(i):-</em></u>
By using trigonometry formulas
a)
cos2∝ = 2 cos² ∝-1
cos∝ = 2 cos² ∝/2 -1
1+ cos∝ = 2 cos² ∝/2

b)
cos2∝ = 1- 2 sin² ∝
cos∝ = 1- 2 sin² ∝/2

<u><em>Step(i):-</em></u>
Given

we know that trigonometry formulas

1- cos∝ = 2 sin² ∝/2
Given

put ∝ = 315

multiply with ' 2 sin (∝/2) both numerator and denominator

Apply formulas

1- cos∝ = 2 sin² ∝/2
now we get

b)

put ∝ = 330° above formula



c )

put ∝ = 315° above formula


d)
cos∝ = 1- 2 sin² ∝/2
put ∝ = 330°

cos 330° = 1- 2 sin² (165°)
Answer:
x=-1539/445, y=1724/445. (-1539/445, 1724/445).
Step-by-step explanation:
y=9x+35
y=-8/9x+4/5
-------------------
9x+35=-8/9x+4/5
9x-(-8/9x)=4/5-35
9x+8/9x=4/5-175/5
81/9x+8/9x=-171/5
89/9x=-171/5
x=(-171/5)/(89/9)
x=(-171/5)(9/89)
x=-1539/445
y=9(-1539/445)+35
y=1724/445
1.46 points put them all in to decimals so 4.26-3.5= .76 + .7 is 1.46
Answer:
de answer is A
Step-by-step explanation:
hope i helped