ANSWER

EXPLANATION
The given angle is 870°.
870°-360°-360°=150°
This means that:
870° is coterminal with 150°, hence its terminal side is in the second quadrant.
It makes an acute angle of 30° with the x-axis.
Note that cotangent is negative in the second quadrant,
Hence,

The first option is correct.
Answer:
+5 and -3
Step-by-step explanation: It gained 5 in value which is +5. It loses 3 in value which is -3.
Answer:
A
Step-by-step explanation:
The equation of a circle in standard form is
(x - h)² + (y - k)² = r²
where (h, k) are the coordinates of the centre and r is the radius
Here (h, k) = (- 2, 3) and r = 3 , then
(x + 2)² + (y - 3)² = 9 ← expand left side using FOIL
x² + 4x + 4 + y² - 6y + 9 = 9 ( subtract 9 from both sides )
x² + y² + 4x - 6y + 4 = 0 → A
We know that sin2x=2sinxcosx
(search the net for proof if you wish)
So the original equation becomes
2sinxcosx-sinx=0
The two terms both have sinx that can be taken out to get:
sinx(2cosx-1)=0
This is true if sinx=0 or 2cosx-1=0 , rewritten: cosx=1/2
sinx=0 than x=2kπ
cosx=1/2 than x=π/3+2kπ
where k is an integer
Hello from MrBillDoesMath!
Answer:
81 ft^2
Discussion:
The area of a square is (length of a side)^2. In this case,
Area = 9^2 = 81
Regards,
MrB
P.S. I'll be on vacation from Friday, Dec 22 to Jan 2, 2019. Have a Great New Year!